How does one prove that a real valued periodic, continuously differentiable function $f(x)$ such that $$f(x)+f'(x)\geq 0$$ must be non negative?  I have no counterexample, but do not know how to prove this with the Mean Value theorem.

Let $f: \Bbb R \to \Bbb R$ be a function such that $f'(x)$ exists and is continuous over $\Bbb R$. Moreover, let there be a $T > 0$ such that $f(x + T) = f(x)$ for all $x \in \Bbb R$ and let $f(x) + f'(x)\ge 0$ for all $x \in \Bbb R$.      Show that $f(x) \ge 0$ for all $x \in \Bbb R$.   My attempt: $f(x) \ge 0 \iff f(x) \ge f'(x) - f'(x) \iff f(x) + f'(x) \ge f'(x)$.  Thus, it is enoguh to show that $0 \ge f'(x)$.  $\iff 0 \ge \lim_{h\to0}\frac{f(x + h) - f(x)}{h}$  I do not know how to proceed from here. I know that $f'$ also has a periodicity of T but I do not know how to use that here.  Am I on the right track? How can I use the periodicity of $f$ to solve the problem?


I'm having some troubles to create a new field in a postgis layer.This is the code I'm trying to use, but nothing happens, no field is created:  from PyQt4.QtCore import *  dbnam = "pruebapython" uri = QgsDataSourceURI() uri.setConnection("localhost", "5432", dbnam, "postgres", "xxxxxxx")     uri.setDataSource("", "masa", "geom","","gid")  layer = QgsVectorLayer(uri.uri(),"masa","postgres") #layer = QgsVectorLayer('/xxx/xxx/xxxxx/xxx/xxx/DatosTest/MASA.SHP', 'MASA', "ogr") layer.startEditing()  layer.dataProvider().addAttributes([QgsField("mytext", QVariant.LongLong )]) layer.updateFields() layer.commitChanges() idx = layer.fieldNameIndex( 'mytext' ) if idx == -1:     print "No field" else:     QgsMapLayerRegistry.instance().addMapLayer(layer) print 'Done!'   If I uncomment the layer which is a shapefile and I comment the posgres one, the field is created perfectly. What am I missing? Could anyone help me?  The QGIS log shows this:  Consulta errónea: ALTER TABLE "masa" ADD COLUMN "mytext"  devolvió 7 [ERROR:  syntax error at end of input             LINE 1: ALTER TABLE "masa" ADD COLUMN "mytext"]   How can I solve this?

I'm having trouble adding a field to a PostGIS table using PyQGIS. Here's my code:  from PyQt4.QtCore import QVariant from qgis.core import *  inLayer = iface.activeLayer() provider = inLayer.dataProvider()  # add field field = QgsField('test_field', QVariant.String) inLayer.startEditing() provider.addAttributes([field]) inLayer.updateFields()  # commit inLayer.commitChanges()   The commit fails and the PostGIS log shows an error:     2015-10-27T08:13:28    1   Erroneous query: ALTER TABLE "received"."env" ADD COLUMN "test_field"  returned 7 [ERROR:  syntax error at end of input      LINE 1: ALTER TABLE "received"."env" ADD COLUMN "test_field"    Seems the call to PostGIS fails to include the column type. Is this a bug, or am I going about this the wrong way?


I have a movie stored on PC harddrive. I have an andriod tablet. How to watch that movie, but on a tablet? How to stream it? Its a windows 10 PC, and its configured for sharing but I dont know how the tablet can find the shared folders and click and play the movie. Kodi works, but Im looking for something simple, as Im not building an entertainment library, just a way to instantiously switch from PC to tablet.   edit: sounds straighforward, but for some reason cant find the answer to this. None of the apps I tried work to achieve this.

I use Ubuntu12.10 with Gnomeshell.  Installed latest version of samba share, configured to share my Video folder, access restricted via login (uid and password needed).  SMB share accessed via Solid explorer when I tried to open the video file (size 600MB, type MKV) the player used BS Player MX Player were not able to play the file.. it says buffering and stops...  Any one has a solution to play video from Shared drive on Android?


I was trying to load pages changing the last value of the url. It seems to work only with the last number (j=19). I don't undestand why it seems to skip the other pages.  <!DOCTYPE html> <html> <head> <script> function newIP(n) {     window.location.replace("@@@@@:"+n)  } </script> </head> <body>  <script> var j; for (j=0; j<20; j++) {     window.setInterval(newIP(j), 1000); } </script> </body> </html>

How would you explain JavaScript closures to someone with a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?  I have seen  given on Wikipedia, but unfortunately it did not help.


how do i re-enable a uninstalled system file on my Moto G Stylus XT2043-4? it only shows up on alternate user accounts. and not my main. i knew this was a bad idea. it basically destroyed my allowing external media to be granted editing capability. OTG too ofc. but i found CX File Explorer that forces a choice now in every single "open as" dialog, cause Files.apk was PAINFULLY SLOW, you see? i hated it! my coldboot times are also PAINFUL. i will do a factory reset if i can backup to my 128gb. i know! i know! i can simply just save everything via USB! but my transfer rates are slow as HECK! my Crucial 8gb. 500gb Crucial SSD. Thinkpad W500 is still a potato. i used: pm uninstall -k --user 0 but i put it back with adb shell pm install i believe i used -d and -r or was it -t whoever helps me out, can you tell me what these do? i used chocolatey in it's C:\ProgramData\chocolatey\bin via hold down shift, then right click! Anyway... whatever i did, powershell gives an error of: Unable to open Files.apk Consider using a file under /data/local/temp where is this location? and will it help? whenever i try to reinstall Files.apk? it's not in root directory of C drive or ProgramData. i know i can simply do a factory reset but... i rather wait.

I got a samsung galaxy folder 2:  It runs Android 6.0.1 Anyways I am not new to ABD and have used it to uninstall system apps on my other phone (Samsung S10) with no problems. So when I got the folder 2 and started removing system apps using pm unistall -k --user 0 as I did with my other phone. Then I decided to remove the contacts app (com.android.contacts) because I installed google contacts. Well apparently, in doing so that contacts app actually housed the phone app as well. So now I have no phone app on my phone. That's kind of a big deal. How do I re enable the contacts app using ADB? My device is not rooted and I don't want to root it. Also I know factory resetting should fix this, but I'd prefer not to do that either. Thanks.


I have been thinking about these amazing images of ancient galaxies we can see because of gravitational lensing. Some of them even have multiple images of the same galaxy in two different places around the lens. We know that with some traditional glass lenses we can reverse the image backwards out of the lens in the direction it came.   Is it possible to see our home galaxy the Milky Way as an image from a gravitational lens refracted back toward us? What would it take to be able to identify and confirm it was actually the Milky Way? I imagine the image would be of the Milky Way many millions of years in the past simply because of the distance such an image would have to travel.  Is there any ongoing research in this field?

Gravitational lensing is an observed phenomenon. Can one have a gravitational mirror?   A slightly unrelated question: Can gravitational waves be reflected?


I would like to know whether these phrases "English Department" and "Department of English" have the same meaning. Thanks!

I would be very grateful for some advice on how to decide whether to use an attributive noun or the "of genitive" (periphrastic genitive).  It seems to me that an attributive noun is generally preferable, except when it leads to ambiguity, often due to the combination of several modifiers with mixed dependent relationships.  Additionally, the of-genitive, when used stand-alone, seems to impart a more formal tone, a higher register.  Simple examples (preferred first, less-preferred second):  The department secretary vs. the secretary of the department.  But:  The excellent secretary of the department vs. the excellent department secretary.  Any additional guidelines would be most welcome.


Can some please explain to me this code   def zap():     print stype  def main():     if True:         stype="something"         zap()          else:         stype="something else"  if __name__ == '__main__':     main()   stype is already defined before I called zap function  But I'm getting this error.  Traceback (most recent call last):   File "C:\Users\x126\Desktop\ss.py", line 12, in <module>     main()   File "C:\Users\x126\Desktop\ss.py", line 7, in main     zap()   File "C:\Users\x126\Desktop\ss.py", line 2, in zap     print stype NameError: global name 'stype' is not defined

How can I create or use a global variable in a function?  If I create a global variable in one function, how can I use that global variable in another function? Do I need to store the global variable in a local variable of the function which needs its access?


Let $f:\mathbb{R} \rightarrow \mathbb{R}$ be a differentiable function. Suppose that there is a constant $B$ such that $\left| f^ı\left( x\right) \right| \leq B$ for all $x$ in $\mathbb{R}$. Prove that $f$ is uniformly continuous.  Can you give a hint?

Suppose that $f$ is a real-valued function on $\Bbb R$ whose derivative exists at each point and is bounded. Prove that $f$ is uniformly continuous.


I just started learning Python, and created the following class, that inherits from list:  class Person(list):     def __init__(self, a_name, a_dob=None, a_books=[]):         #person initialization code         list.__init__(a_books)         self.name = a_name         self.dob = a_dob   However, there are three things I don't understand:   This line list.__init__(a_books), doesn't actually initialize my instance's list of books. I am supposed, according to the book, write list.__init__([]) instead. Why is this step necessary. Why is there no reference to self in list.__init__([])? How does Python know?

I'm trying to understand the use of super(). From the looks of it, both child classes can be created, just fine.   I'm curious to know about the actual difference between the following 2 child classes.  class Base(object):     def __init__(self):         print "Base created"  class ChildA(Base):     def __init__(self):         Base.__init__(self)  class ChildB(Base):     def __init__(self):         super(ChildB, self).__init__()  ChildA()  ChildB()


I am trying to install an old AMD driver for my laptop on Kubuntu (Ubuntu 20.10 - groovy), but I get "following packages have unmet dependencies" issues for libqtcore4 and lib32gcc1. Details I have downloaded the deb files from , and I have written this script to install them. sudo apt-get update sudo apt-get install build-essential sudo apt-get install dkms sudo apt-get install ./fglrx-core_15.201-0ubuntu1_amd64_UB_14.01.deb ./fglrx_15.201-0ubuntu1_amd64_UB_14.01.deb ./fglrx-dev_15.201-0ubuntu1_amd64_UB_14.01.deb ./fglrx-amdcccle_15.201-0ubuntu1_amd64_UB_14.01.deb  However, I get these errors:  The following packages have unmet dependencies:  lib32gcc1 : Depends: gcc-10-base (= 10.2.0-5ubuntu1~20.04) but 10.2.0-13ubuntu1 is to be installed E: Unable to correct problems, you have held broken packages. ... The following packages have unmet dependencies:  fglrx : Depends: libqtcore4 (>= 4:4.7.0~beta2) but it is not installable  fglrx-core : Depends: lib32gcc1 but it is not installable E: Unable to correct problems, you have held broken packages.   How can I install these dependencies? Is there an unofficial package that allows me to do this? My graphic card is a dual Radeon HD 6400M/7400M series + Intel HD 3000. Currently, the Intel graphic card is chosen using Mesa drivers, but I want to switch to AMD. I am OK with any unofficial driver that works.

I have 14.04.5/16.04 or newer and an AMD GPU. I'm not getting the performance I want, and some programs say they need things like OpenCL.  I've heard about fglrx, but if I try to install it on my machine, it breaks and I have no GUI.  Is there anything I can do to get my AMD card working to its full potential?


I am using the aer bibliography style with BibTeX. I am wanting to write out citations in the text with three or more coauthors. An easy way to do this is to use \citet*, \citep*, etc. as opposed to \citet, \citep, etc. However, there is no Oxford comma. How can I get it to include a comma before the and?  Note that this has been asked, but not answered, in a comment by @user67403 (the last comment on the question) here:

For aer.bst, citations with 3 or more authors are listed using et al. I need to modify the bibliography so that citations with 4 or more authors are listed using et al., but that citations with 3 authors have all the names written out. For example, I want "See Adams, Brown, and Clark (2003)" as opposed to "See Adams et al. (2003)." I'm using natbib with LaTex: \usepackage{natbib,har2nat}  In order to do that, I need to modify the function format.lab.names.abbr.  Might someone know how to do this?  FUNCTION {format.lab.names.abbr} { 'name.list :=   name.list num.names$ 'numnames :=   numnames #1 >     { numnames #2 >         { name.list #1 "{vv~}{ll}" format.name$ " et al." * }         { name.list #2 "{ff }{vv }{ll}{ jj}" format.name$ "others" =             { name.list #1 "{vv~}{ll}" format.name$ " et al." * }             { name.list #1 "{vv~}{ll}" format.name$ " and " *               name.list #2 "{vv~}{ll}" format.name$ *             }           if$         }       if$       field.used editor.field = {", eds" *} {} if$     }     {         name.list #1 "{vv~}{ll}" format.name$         field.used editor.field = {", ed" *} {} if$     }   if$ }   FUNCTION {format.lab.names.full} { 'name.list :=   #1 'nameptr :=   name.list num.names$ 'numnames :=   numnames 'namesleft :=     { namesleft #0 > }     { name.list nameptr "{vv~}{ll}" format.name$ 'temp :=       nameptr #1 >         { namesleft #1 >             { ", " * temp * }             { temp "others" =                 { " et~al." * }                 { " and " * temp * }               if$             }           if$         }         'temp       if$       nameptr #1 + 'nameptr :=       namesleft #1 - 'namesleft :=     }   while$   numnames #1 > field.used editor.field = and {", eds" *} {} if$   numnames #1 = field.used editor.field = and {", ed" *} {} if$ }


After reading an article on Schrodinger's Cat, it seems that if we take the environment as an observer, that superposition cannot occur because all atomic and subatomic entities would be observed all the time. Thus, something like quantum entanglement cannot occur. So if superposition cannot occur, why is superposition (and by extension quantum entanglement) still part of quantum mechanics?  Updated: In the question , the notion of observer is replaced by measurement. In this context, my question would be: if the system (cat) is constantly being measured by the environment (the observer is watching the cat), how can superposition (the cat is in multiple states; i.e., alive and dead) exist in quantum mechanics?  For example, if a photon passes by a heavy particle and splits into an electron and positron, the splitting process is a measurement of the electron and positron to make sure the total spin is 0. I understand the argument that we might not know which has +1/2 and which has -1/2, but the observation/measurement had to be done to make sure we didn't have 3/4 total spin.

I don't understand how quantum mechanics (and therefore also quantum computers) can work  given that while we work with quantum states, particles that this quantum state consist of cannot be observed, which is the most fundamental requirement.  If I am not mistaken, by "observed" we mean interaction with any other particle (photon, gluon, electron or whatever else). So my very important questions:   Aren't the particles this quantum state consists of interacting with each other? Why doesn't that cause the state to collapse? Aren't all particles in the universe interacting with Higgs field and gravitons etc? Why doesn't that cause every quantum state to collapse?   I feel there is something very fundamental in quantum mechanics that I am not aware of, hence I would be very pleased to have these questions answered.


Java, c, c++ both have syntactic sugar like this:  int a = condition ? c : d// if condition is true , a = c, else a = d   Do python have similar syntactic sugar?

If Python does not have a ternary conditional operator, is it possible to simulate one using other language constructs?


I am planning to get a Microsoft surface 3. I am wondering that can I download MikTeX and TeXstudio or other LaTeX softwares. I found a same question at this post . But this post is before Surface 3 release.   Thanks

I have my new Microsoft Surface and I was wondering whether it's possible to install pieces of software like MikTeX and TexMaker on this tablet. Does anyone know?


What is the term for a word that has come to mean the opposite of its original meaning"

Is there such a thing in the English language as words or phrases that can mean a something or its opposite depending on the context in which they are employed, without the use of sarcasm?   If so, how are they named?


I downloaded cruft-0.2.tar.gz and extracted the files into a directory. Here is the list of files:  COPYING        cruft.1  cruft.doc  INSTALL   keygen.c  packing.list cruft-0.2.lsm  cruft.c  cruft.h    keygen.1  Makefile   How do I install this program? I am using Ubuntu 16.04 LTS

I have downloaded tar.gz files. But I don't know how to install it. How do I install this kind of file?


Currently if an answer is deleted while you're writing a comment on it, you don't get notified until you press Enter to submit the comment. I find that very jarring, especially due to the bright red color. It's also annoying to get it after spending the better part of a minute writing a clear comment.  It would be nice if we could get an orange bar saying that the answer has been deleted while we're writing the comment, instead of the red popup when submitting it.

At the moment SE shows us current voting results, a notification for new answers and comments, etc., instantly. However, it doesn't show us when a post is deleted.  Please notify us also when a post is deleted. Then I don't have to type a (long) comment, only to notice the post got deleted in the meantime.


I have 2 differents 'free space' digits. And after delete something big from disk -> free space in 'About your mac' - still unchanged.

I wanted to know what was the free available space in my internal HD (I actually have a SSD). In Finder, if I trust the Show Info information (right click or cmd+I on Macintosh HD icon in the Finder sidebar) I get a certain available space. Otherwise, if I just press the spacebar (quick insight), I get a different value, it seems that it's not updated. Finally, also Disk Utility reports a different value.  Why these three different values?  (this gap first appeared after upgrading to El Capitan and trash is already empty).  Available space displayed when clicking Show Info:    Available space displayed when pressing spacebar:    Available space displayed in Disk Utility:


The Hot Network Questions tab exists on many sites. It is (almost) always dark-ish text on a white background. Usually, links that I've clicked on before change color, which helps me keep track of what I've seen before.  The problem is that that's not the case on all sites. On some sites, the links are blue by default, and turn dark when clicked. On others there's barely any difference at all.  Please make the links have the same colors on all sites.  Some examples: Visible just fine:  Hard to see:  Impossible:

This is a HNQ excerpt from Stack Overflow. Visited questions are objectively darker.    This is a HNQ excerpt from Super User. Visited questions are objectively lighter.    This is a HNQ excerpt from Seasoned Advice. Visited questions are objectively darker.    This is a HNQ excerpt from Puzzling, a beta site. Visited questions are objectively darker, although the difference is hard to spot.    This is a HNQ excerpt from Travel. Visited questions actually have a completely different color.    These are 5 different sites, with 5 different formats for how the HNQ sidebar displays links. Some make visited links darker. Some make them lighter. Some make them a little big darker. some give visited links a completely different color. This is very confusing: If someone visits one of these HNQ questions and wants to continue browsing the HNQ from there, they likely expect that the links in that HNQ segment have consistent layout compared to the HNQ segment from the website they came from.  Is this something worth looking into? I realize that each site has their own look and feel, but an element that appears on every site should be consistent IMHO. People have expectations about how links work, and one of those is that if you click on a link within the same domain (which the HNQ segment arguably is), they behave similary on that page as they do on the page you come from.


I put some 8Gb MicroSD card in Video Recorder and recorded some video onto it. Then I got a message, that card is full. I plugged it into computer's card reader and saw, that card was full of Android filesystem files from some old device. Also I found two video I just recorded. I saw these videos and at the moment I was watching second one I got a message, that data is unreadable.  After that when I am looking at the card I only see System Volumne Information directory from Windows and one big 3.5G file with garbaged name. This file probably encapsulates entire flash card content.   I can't open or copy this file.  How can I restore data in this situation?

I had a 500gb ssd which went bad today. I removed it and connected it to another computer. The name of the drive appears to have weird symbols. And the drive appears to have 11TB memory.    Can this drive be fixed. Can I recover data from it?


I would like to know what do I have to do if I want to convert the my Tex document into an image.  I'm new to Latex World, sorry if it is a dumb question for somebody

I need to convert my LaTeX documents into PNG. The problem is, I also need the resulting image to be as short as possible (height-wise). I've tried latex followed by dvipng, but the result is always the size of a page. For instance, take a .tex file containing:  \documentclass{article}   \begin{document}   Hello. This is a test. \begin{equation}   L = 2                                                                      \end{equation}   \end{document}   If I compile it with latex, and then run dvipng, I get a PNG file that's the size of a full page. What I need is for the PNG file to be only as tall as needed for everything to fit. So the image would end immediately after the equation. The image still needs to have full width (because of the equation numbering).  Is there a way to achieve that?


I use a lot of garlic in my cooking, especially minced garlic.  But lately I've been doing some more recipes with crushed garlic and while I love the texture of cooked garlic, I can't see how it could be better than minced garlic for the overall taste.  Is there an advantage to crushed garlic over minced garlic, beyond texture?

Often recipes say to chop garlic, but I usually cheat and just crush it as it's quicker. Is there any difference in doing this? Will it have much of an effect on the flavour of the dish?


I have downloaded Oracle 18C XE the rpm file, but I don't know how to install the database.

I have a burning desire to install RPMs onto my Ubuntu installation - is this possible? Can I use Yum - or another RPM Package Management tool?


I want to avoid check if a particular function is returning true, and perform an action (Set Active) once it does return true for the first time.  Currently my code looks like this:  Update() {         if ( IsTaskCompleted() ) {             object.SetActive( true );     } }   SetActive gets called every frame after the task is completed. How can I avoid this, and call SetActive only once?

I have some code that I only want to run once, even though the circumstances that trigger that code could happen multiple times.  For example, when the user clicks the mouse, I want to click the thing:  void Update() {     if(mousebuttonpressed) {         ClickTheThing(); // I only want this to happen on the first click,                          // then never again.     } }   However, with this code, every time I click the mouse, the thing gets clicked. How can I make it happen only once?


How should I solve the problem on the out put of a bibliography when capital letters change to Lowercase letter.  For Example, it should be:      AR Setoodeh and M Shojaee. Application of TW-DQ method to nonlinear free vibration analysis of FG carbon nanotube-reinforced composite quadrilateral plates. Thin-Walled Structures, 108:1–11, 2016.   but it shown:     AR Setoodeh and M Shojaee. Application of tw-dq method to nonlinear free   vibration analysis of fg carbon nanotube-reinforced composite quadrilateral   plates. Thin-Walled Structures, 108:1–11, 2016.    \documentclass{book}     \setcounter{tocdepth}{3}     \begin{document}     The DQ method as an efficient and accurate numerical tool is     applied to discretize the nonlinear governing differential equations      and the related boundary conditions in the spatial domain.     The new transformed weighting coefficients are developed and     introduced to make the procedure more systematic for the case of     quadrilateral plates. For this purpose, a two-dimensional geometric      transformation is constructed to express the derivatives in     the physical domain in term of the derivatives in the computational       domain x-y (see Fig. 3). The transformation procedure for     the first- and second-order derivatives of an arbitrary function is     presented in Appendix A.   \cite{setoodeh2016application}     {     \bibliographystyle{plain}     \bibliography{MyReferences}     }     \end{document}   Also, my bib Reference file is as,  %%%%MyReferences.bib   @article{setoodeh2016application,   title={Application of TW-DQ method to nonlinear free vibration analysis of FG carbon nanotube-reinforced composite quadrilateral plates},   author={Setoodeh, AR and Shojaee, M},   journal={Thin-Walled Structures},   volume={108},   pages={1--11},   year={2016},   publisher={Elsevier} }   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Titles of articles I'm about to cite contain upper case letters and when using BibTeX it converts them to lower case ones. This happens only in the title and only the first letter conserves its case. For example, when I cite an article about HF, the reader won't know if it is about Hafnium (Hf) or fluorine acid (HF).  I know that I can fix it manually in the .bbl file but I would like to avoid it, or fix it automatically.


I take it an ARM MCU can be run without an OS - at which point might it become necessary to install one?  Can the mbed SDK run without the mbed-os or any other mbed for that matter?

I have written plenty of bare metal code for PIC and x86 processors.  Can someone tell me how and when should I need an operating system?  Conversely, what application or situation can be dealt with or without an operating system as well?


Hank and Marie are happily married, except for small issues like when Marie was klepto. There is no hint in the show and I can't think of any reason why Hank and Marie have no kids. Is there a certain angle that needed this to make the show's plot better by making it more plausible or draw certain emotions in viewers, like the way things happened before Walt is left with his container full of money?

In Breaking Bad it seemed that the Schraders loved White's kids very much and enjoyed having them in their place. Is there in-series explanation why they didn't have their own? Same question about the Schwartzs -- they weren't young, had more than enough money and still didn't have any children.


Why does a light grey T-shirt look dark grey when wet? I think this happens because the water molecules get stuck in the fabric and reflect light in different ways(different wavelengths) compared to the reflection that occurs when the cloth is not wet.  Is this right or are there other reasons?

When something gets wet, it usually appears darker. This can be observed with soil, sand, cloth, paper, concrete, bricks...  What is the reason for this? How does water soaking into the material change its optical properties?


I have 3 NPCs in my "Game". When the player walks up to any of them, they're supposed to have their own dialogue; I've tested this, and they do.  I tried to create a display that shows this dialogue text using a TextMeshProUGUI attached to a blank GameObject called dialogDisplay (tagged DialogDisplay). There is one DialogDisplay object in the scene that I'm trying to get each of my NPC's to use. I tried to make the display object inactive in the NPC Start() function, and enable it when it's time to display the NPC's next sentence.  When I run my game, I get an error on line 21, where SetActive() is called: "Object Reference Not Set to an Instance of an Object".  Here's the NPC script (DisplayNextSentence() is at the bottom, where dialogDisplay is used):  public class NPC : Character { private bool charInRange; public Dialogue dialogue; public bool talkedTo = false; private Queue<string> sentences; public TextMeshProUGUI textPro; public GameObject dialogDisplay; private bool isTalking;  // Use this for initialization void Start () {     charInRange = false;     textPro = FindObjectOfType<TextMeshProUGUI>();     dialogDisplay = GameObject.FindGameObjectWithTag("DialogDisplay");     dialogDisplay.SetActive(false); }  // Update is called once per frame void Update () {     //if player is in range and presses space, triggers NPC dialogue     if (charInRange && Input.GetKeyDown(KeyCode.Space))     {         TriggerDialogue();     } }  //if Player gameObject is in NPC collider, player is in range void OnTriggerEnter2D(Collider2D other) {     if(other.gameObject.tag == "Player")     {         charInRange = true;     } }  //if player exits NPC collider, player is not in range void OnTriggerExit2D(Collider2D other) {     if (other.gameObject.tag == "Player")     {         charInRange = false;     } }  //if NPC has been talked to before, displays next sentence; if not, loads dialogue and displays first sentence private void TriggerDialogue() {     if (!talkedTo)     {         talkedTo = true;         StartDialogue(dialogue);     }     else     {         DisplayNextSentence();     } }  //loads a queue with lines from Dialogue and displays first sentence public void StartDialogue(Dialogue dialogue) {     sentences = new Queue<string>();      foreach (string sentence in dialogue.sentences)     {         sentences.Enqueue(sentence);     }      DisplayNextSentence(); }  //displays next sentence in the queue public void DisplayNextSentence() {     string sentence;     bool done = false;      //if last sentence in the queue, display it again     if (sentences.Count == 1)     {         sentence = sentences.Peek();         textPro.text = sentence;         Debug.Log(sentence);         return;     }      sentence = sentences.Dequeue();     textPro.text = sentence;     dialogDisplay.SetActive(true);     while (!done) {         Debug.Log("In WHile Looop");         if (Input.GetKeyDown(KeyCode.A))         {             done = true;         }     }     dialogDisplay.SetActive(false); } }   Grateful for any insight or tips you can provide. Happy to provide further information if it helps. Thank you!

Since many users are facing the NullReferenceException: Object reference not set to an instance of an object error in Unity, I thought that it would be a good idea to gather from multiple source some explanation and ways to fix this error.  Symptoms I am getting the error below appearing in my console, what does it mean and how do I fix it?  NullReferenceException: Object reference not set to an instance of an object


i know that java is call by reference, i have a question about these code  public class test {  public static void main(String[]  argv){       ArrayList<Integer>  a = new ArrayList<Integer>();     int aa = 5;     int[] aaa ={0,1,2};     a.add(1);     aaa[0]=999;     System.out.println("ArrayList "+ a.toString());     System.out.println("int "+ aa);     System.out.println("Array "+ Arrays.toString(aaa));      add2(a,aa,aaa);       System.out.println("ArrayList"+ a.toString());     System.out.println("int "+ aa);     System.out.println("Array "+ Arrays.toString(aaa)); }  private static  void add2(ArrayList<Integer> a1,int aa1,int[] aaa1) {     a1.add(2);     aa1=aa1+10;     aaa1[2]=999; }   the result is  ArrayList: [1]  int:       5  Array:     [999, 1, 2]  ArrayList: [1, 2]  int:       5  Array:     [999, 1, 999]   why ArrayList  and Array will change when i call function and "int" won't change  Can someone explain to me these situation  , thanks a lot

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


I have electrical engineering this semester and there is this thing bugging me this whole time, how to see which resistors (or whichever component) are connected in which way?   I can do it by following where current divaricates, but it gets a little tricky when I have circuits like this below.  Do you have any tips?  (We don't know if all resistors are the same value or not !)

This is probably a very basic question but I have the following circuit, I am not sure what is in series and what is in parallel or if they are all in parallel, initially I thought R2 and R3 were in series and then used the sum of their resistances with R1 to calculate the equivalent resistance, that seems to be  off based on some circuit simulation software I am using so I would appreciate if somebody could explain how to calculate the Rt and the logic behind it.  Thanks.          – Schematic created using


How do I list all package names in one section? If, for example, I want to list all applications in section "web", which command do I need to input?

In Synaptic, one can list packages by section. For example, in the image below all packages of the "Amateur Radio (universe)" section are listed.  How can I get such a list (edit: with package description) at the command line?  I need a raw list; a terminal application like aptitude will not do.


I have a road bike and I got a flat tire probably after going back on the road from the sidewalk very carefully. I guess I pinched my tire.   I usually inflate my tires to 7 bars. Is it enough and can I avoid this kind of issues with a higher pressure?  I also discover that I can replace my tires with some with Kevlar on it. Is it a good alternative?

There's a question for mountain bike tyres but I can't seem to find anything on here for road bikes. At the moment I'm running at around 90psi. Is that too much? too little?  Also, am I more likely to get punctures running at higher pressure?  I seem to be getting a lot lately.


Let $$f:X\rightarrow Y,$$ where X and Y are metric spaces and Y is compact. If  f  has a closed graph $$G_f=\{(x,f(x)):x\in X\},$$  then f is continuous.   My first instinct is to use the fact that if $${x_n}\rightarrow x \;\text{  and  }\; \{f(x_n)\} \rightarrow y$$ implies x is in X and f(x)=y, then showing the f is continuous at $(x,y)$, and so continuous on X. Having trouble getting direction on this.

This is the analogue of closed graph theorem for compact space          Suppose that $X$ and $K$ are metric spaces, that $K$ is compact, and that the graph of $f: X \rightarrow K$ is a closed subset of $X \times K$. Prove that $f$ is continuous.      Because metric space is first countable, all we need is to prove that if $x = \lim_{n \rightarrow \infty} x_{n}$, then $f(x) = \lim_{n \rightarrow \infty} f(x_{n})$. Suppose $x = \lim_{n \rightarrow \infty} x_{n}$, then because $K$ is compact, sequence $\{f(x_{n})\}$ has a subsequence $\{f(x_{n_{i}})\}$ converge. Because the graph of $f$ is closed, we must have $\lim_{n \rightarrow \infty}\{f(x_{n_{i}})\} = f(x)$. All we need to prove now is $\{f(x_{n})\}$ converge to $f(x)$, but I can't prove that. Can any one help me. I really appreciate. Thanks


Various questions have come close to this but involve using a browser extension or proxy server or only block the domain and are not questions or answers about leaving a domain unblocked while only blocking access to a specific page on that domain.  For example:        But I'm not asking how to: 1) use a proxy (because I use opendns already), 2) use a browser extension (because I need it to work on all browsers), 3) block a whole domain,       But I must only block access to only a specific page on a domain such as www.example.com/page. and can not use proxies or extensions because I need a solution for a whole business network. This is not just my home computer I'm talking about here.  Unlike some of the questions linked above, I need to specifically block only certain pages on a webpage, and I don't want to block the entire domain or use a browser extension.

I want to block certain URLs on browsers. I don't want to block whole site. For example, I want to block , but not whole  domain. Is there any way I can do it?


So me and my friends manged to make a server in Minecraft for us to play on and we would like to add mods. But the mods we want to add are a few versions lower than the updated version. Is there any way of making a server with a lower version of Minecraft that people can still play on?

I am trying to set up a Tekkit-like server (+ some different mods). Most mods are not 1.4.2-compatible, yet, so the server runs 1.3.2. I can use MCNostalgia to downgrade the client, but is there any way to downgrade the server or download an old version?


Why does the following code print out 6 and not 20?  public class ClassA {     public static void main (String [] args ) {         int k = 5;         doub ( k );         doub ( k );         if ( k <= 19) {             k ++;         }         System. out . println ( k );     }     public static void doub (int x ) {         x *= 2;     } }   Thanks in advance.


I wonder if someone can help me with a caml-query. I want to retreive list items from different list that has the column name "Link". But it should only retreive if the column has a value. How can I solve this with CAML-query?   Right now I tried to solve it with an if statement. But I get "undefined" and "null" because some of the list has the column name without any value or the list doesnt have the column name "Link".  Thanks!

I am creating a hosted app in SharePoint. I want to retreive all the custom list from SharePoint and then from the custom lists I want to fetch column values. I got 2 columns with the names title and link. Link is a hyperlink column containing urls. My question is some of my custom lists doesnt have the column name "link" and some has. But I want to retreive those list that has that column. And title column is in every custom list. Some of the list has the column name "link" but with no values.  Error message: 0x800a138f - Runtime errors in JavaScript: Unable to retrieve the property get_url for a reference that is undefined or null      function onSuccessItemFetch() {     // Now you can access the array of SP.ListItemCollection     for (var i = 0, length = listItemsCollection.length; i < length; i++) {         var items = listItemsCollection[i];         var enumerator = items.getEnumerator();          while (enumerator.moveNext()) {             var listItem = enumerator.get_current();             if (typeof listItem.get_item('Link') != "undefined" && typeof listItem.get_item('Link') != null) {             itemString += listItem.get_item('Title') + "&nbsp" + "&nbsp" + "&nbsp" + "&nbsp" + "&nbsp" + "&nbsp" + "" + "öppna formulär" + "" + "
";  //oListItem.get_item('Datum')             $('#divAllaListItems').html(itemString);             }         }     } }   It works fine when I want to retrieve all the custom list titles and the title column values.


In Deep Breath (series 8) the Doctor tries to remember a previous incident with      clockwork androids stealing human body parts to repair machinery.   Yet he can't. During another conversation with the episode's main "villain", he finally remembers a few parts of his own history.  He's looking at the backside of some kind of fuse and reads the name      SS Marie Antoinette   and shortly later combines this with the name of the supposed sister ship:      SS Madame de Pompadour   The actual event he remembers has been depicted in an episode of series 1 (2005).      However, as far as I remember, at the end of The Girl in the Fireplace the Doctor just kept wondering why the droids wanted Madame de Pompadour specifically. As far as I know it's only shown to the audience that the ship's hull has Madame de Pompadour written on its flank, essentially revealing its name.   So did I just miss the Doctor noticing the name? Or is this a plot hole?

In season 8 episode 1, when the Doctor encounters the episode's villain(s), he keeps saying that this is all very familiar to him, but he can't quite put a finger on it. Is this a case where the audience is supposed to know more than the Doctor (like when he can't keep Clara and Strax straight), or is he referring to something we (the audience) haven't seen yet? As in, are the serious Whovians yelling at the screen, "it's [insert name of classical Dr. Who villain here]!", or are they as puzzled as the Doctor is (and I am)?


I have a model named Student. This is a Java RMI program. I declared the Student Serialized Object in client side. I got following error.      SEVERE: null java.rmi.UnmarshalException: error unmarshalling return; nested exception is:      java.io.InvalidClassException: com.simulator.model.Student; local class incompatible: stream classdesc serialVersionUID = -6650366980271983195, local class serialVersionUID = 6359019065551364622     at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:173)     at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:178)     at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132)     at $Proxy2.performList(Unknown Source)     at com.simulator.ui.student.AddNewStudent.<init>(AddNewStudent.java:90)     at com.simulator.ui.main.Home$3.actionPerformed(Home.java:109)     at org.pushingpixels.flamingo.api.common.AbstractCommandButton.fireActionPerformed(AbstractCommandButton.java:614)     at org.pushingpixels.flamingo.api.common.AbstractCommandButton$ActionHandler.actionPerformed(AbstractCommandButton.java:566)     at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)     at org.pushingpixels.flamingo.api.common.model.ActionRepeatableButtonModel.setPressed(ActionRepeatableButtonModel.java:123)     at org.pushingpixels.flamingo.internal.ui.common.BasicCommandButtonListener.mouseReleased(BasicCommandButtonListener.java:147)     at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)     at java.awt.Component.processMouseEvent(Component.java:6263)     at javax.swing.JComponent.processMouseEvent(JComponent.java:3255)     at java.awt.Component.processEvent(Component.java:6028)     at java.awt.Container.processEvent(Container.java:2041)     at java.awt.Component.dispatchEventImpl(Component.java:4630)     at java.awt.Container.dispatchEventImpl(Container.java:2099)     at java.awt.Component.dispatchEvent(Component.java:4460)     at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4574)     at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)     at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)     at java.awt.Container.dispatchEventImpl(Container.java:2085)     at java.awt.Window.dispatchEventImpl(Window.java:2475)     at java.awt.Component.dispatchEvent(Component.java:4460)     at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)     at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)     at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)     at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)     at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)   My Student Class is  public class Student implements Model, Serializable {     public static final long serialVersionUID = 456544542L;     String id;     String name; }   Declaration..  List<Student> performListStd = stdController.performList();         for (Student student : performListStd) {             mpUsers.put(student.getUserName(), student.getStdPass());         }   stdController has MYSQL query for searching.  Thanks in Advance

Eclipse issues warnings when a serialVersionUID is missing.       The serializable class Foo does not declare a static final   serialVersionUID field of type long   What is serialVersionUID and why is it important?  Please show an example where missing serialVersionUID will cause a problem.


Please, I need some clarification on this. If $f$ is continuous and bounded on $\Bbb{R}$, does it mean that $f$ is uniformly continuous on $\Bbb{R}$?

I am thinking about this since couple hour. Is a continuous and bounded function $f:\mathbb R\to\mathbb R$ uniform continuous too? I didn't found a counter example and thus I tried to prove this like this: let $\epsilon>0$ and $a\in\mathbb R$. By continuity, there is a $\delta_a>0$ such that $$d(f(x),f(y))<d(f(x),f(a))+d(f(y),f(a))<\epsilon$$ if $d(x,y)\leq d(x,a)+d(y,a)<\delta_a.$ Then, if $\inf_a\delta_a>0$ I set $\delta=\inf_a\delta_a$ and we are done since $d(f(x),f(y))<\epsilon$ if $d(x,y)<\delta,$ but I didn't success to prove that $\delta\neq 0$.


I run Postfix with Dovecot. Now I need to begin to backup email messages. What directories should I backup? Such that later, if a server breaks down, I'll be able to restore all the email message on a new server with Postfix and Dovecot.

I want to backup all the emails (their content) on a server where I run Postfix, so that later on I'll be able to restore the emails, on other server or locally. Among other folders, I have this: $ ls -al /var/spool/  total 16 drwxr-xr-x  4 root    root 4096 May 22  2018 . drwxr-xr-x 16 root    root 4096 Sep  5 18:28 .. drwxrwxrwt  3 root    root 4096 May 23  2018 mail drwxr-xr-x 18 postfix root 4096 Sep 11 20:01 postfix  What precisely do I have to backup, what folders?


As title, although it is not a good practice to insert any additional button in a built-in menu. What if I meant to do so? bpy.types.Menu only provide menu.prepend(call_func) and menu.append(call_func) to make custom draw method in front or behind the original buttons.   only said it is not possible to reference menus in Blender’s default scripts. So is the concept of draw is working like following code? issubclass(menu, bpy.types.Menu)  if menu.prepend_callback:   for menu_func in menu.prepend_callback:     GUI.draw(menu_func)  GUI.draw(self.draw)  if menu.append_callback:   for menu_func in menu.append_callback:     GUI.draw(menu_func)  And If I really need to do insertion, I will need to insert the menu function directly inside the panels source code?

Blender has a built in template for adding a custom menu to the main header (INFO_HT_header). This can be found by going into the text editor under templates->Python->UI Menu.  Can I relocate this custom menu to be inserted between "Window" and "Help" sub menus? If so, how?


I've a failed drive reported in my RAID5 running on a Dell R710 using RHEL5 with a DELL PERC controller.  Is there a method to determine which drive it is?  Can I do this at the command line?

I have a Dell PowerEdge R415 and R515 and wondering how I can be alerted remotely when a hard drive fails in either server? Both are running RAID, so I need to be notified, so I can swap out the drive. Both servers only have the basic Baseboard Management Controller. Is this possible with a third party tool/software?


I would like to vertically align text next to an image in a before pseudo-element. The way it's working now is that my image is displayed to the left of my text, but both the image and text sit on the same baseline. I tried using vertical-align, but it didn't work. I think the issue is that content is treating both the image and text as one block element.   * {   margin: 0;   padding: 0; }  body {   background-color: #000000; }  header {   background-color: #202830;   color: #ffffff;   width: 100%; }  header::before {   align-items: center;   background-color: #581845;   color: #E88968;   justify-content: center;   content: url("https://stackoverflow.com/favicon.ico") " This is some text";   display: flex;   height: 72px;   width: 100%; }  p {   padding: 16px; }
This is my header
      In the snippet, you can see that "This is some text" is aligned with the baseline of the image. I want it to be centered with the image. Update: This code works in Firefox 82.0.3 (32-bit) on Windows 10, but does not work in Chrome 86.0.4240.198 (64-bit) on Windows 10 or Edge 87.0.664.47 (64-bit) on Windows 10.

I have a div with two images and an h1. All of them need to be vertically aligned within the div, next to each other. One of the images needs to be absolute positioned within the div. What is the CSS needed for this to work on all common browsers?

testing...


The auto comment is added when one flags a question as a possible duplicate. These comments are generated in the form:     possible duplicate of [Question Title] (Link to the question)   With the  of [on hold], unclear etc. to close-votes (and flags; AFAIK users with low rep can still access the close-vote box); I think it's fair to auto-comment for the following cases as well:   Questions asking for code must demonstrate a minimal understanding of the problem being solved. Include attempted solutions, why they didn't work, and the expected results. Please clarify your specific problem or add additional details to highlight exactly what you need. Questions concerning problems with code you've written must describe the specific problem and include valid code to reproduce it. Programming questions are off-topic on Meta Stack Overflow.   (The list is compiled from Stack Overflow and meta Stack Overflow; but can be extended for wider family of network sites)  A majority of questions don't get closed within let's say 5 minutes, and OP isn't notified of close votes received on their posts. The above reasons are pretty widely used and OP has no idea why the questions aren't getting enough attention unless they get down-voted (to eternity).  These auto-generated comments will, of course, be auto-deleted just like in the case of "possible dupes" once the question gets closed or the OP edits their question.

I know that that duplicate questions automatically post the duplicate to the comments on the question.     Would it be possible / a good idea to have this for all vote closes?  Possibly having a check box at the bottom of the vote close window to post reason as a comment to the question might work as well.   My reasoning for this is I tend to vote close questions for lack of effort.       unclear what you're asking - Please clarify your specific problem or   add additional details to highlight exactly what you need. As it's   currently written, it’s hard to tell exactly what you're asking. See   the How to Ask page for help clarifying this question.   Now in some cases the question could be improved, but a lot of times questions like this are by new users who don't always return.  If I feel it can be improved I like to let these new users know that it was vote closed and why.  I copy that to the comment. example:    Is this something we could consider adding?


I have ubuntu 18.04 running on lenovo P53s(5.3.0-59-generic). I have Bose QC 35 II headset paired using bluetooth. The audio is working good, but I am facing a problem when trying to use them as input device. I have two profiles listed for audio output: High Fidelity Playback (A2DP Sink) and Headset Head Unit (HSP/HFP). The former has much better audio quality. If I go to Sound Settings my headphones are listed as input device (I have two options - Internal Microphone - Built-in Audio and Bluetooth input - Bose, the former is selected). However selecting the headphones as input device automatically changes the profile of audio output to Headset Head Unit (HSP/HFP).  This profile results into significantly worse quality of the audio and also I hear the message Call from from time to time. If I try to change the audio profile back the input device also changes back. I would like to be able to use the microphone and at the same time use High Fidelity Playback (A2DP Sink) audio profile. Is this possible?

I have a CEL-TEC F5A headset. The spec says:      Bluetooth 4.0, profiles: Headset, Hands free, A2DP, AVRCP/HSP/HFP   It plays nicely with High Fidelity Playback (A2DP sink) profile.  When I want to switch audio input to the headset's microphone, the output profile automatically changes to Headset Head Unit (HFS/HFP) and the quality is terrible - like 8bit sound or something. When I switch it back to A2DP, the input is back to desktop mic.  I've read few of other questions and seems A2DP is expected not to support input, right? But the HFP part in HFS/HFP is High Fidelity Playback I guess? That sounds like it could work as a headset and still not sound like 1950's phone.  How could I simplify switching between the profiles so that it is HFS/HFP when I talk and A2DP when I listen? E.g. as a push-to-talk.  Ubuntu 17.10, no sound customization IIRC, everything latest.   My output:  $ pactl list cards Card #0         Name: alsa_card.pci-0000_00_03.0 ...  Card #4         Name: bluez_card.00_19_5D_25_6F_6C         Driver: module-bluez5-device.c         Owner Module: 30         Properties:                 device.description = "F5A"                 device.string = "00:19:5D:25:6F:6C"                 device.api = "bluez"                 device.class = "sound"                 device.bus = "bluetooth"                 device.form_factor = "headset"                 bluez.path = "/org/bluez/hci0/dev_00_19_5D_25_6F_6C"                 bluez.class = "0x240404"                 bluez.alias = "F5A"                 device.icon_name = "audio-headset-bluetooth"                 device.intended_roles = "phone"         Profiles:                 a2dp_sink: High Fidelity Playback (A2DP Sink) (sinks: 1, sources: 0, priority: 10, available: yes)                 headset_head_unit: Headset Head Unit (HSP/HFP) (sinks: 1, sources: 1, priority: 20, available: yes)                 off: Off (sinks: 0, sources: 0, priority: 0, available: yes)         Active Profile: a2dp_sink         Ports:                 headset-output: Headset (priority: 0, latency offset: 0 usec, available)                         Part of profile(s): a2dp_sink, headset_head_unit                 headset-input: Headset (priority: 0, latency offset: 0 usec)                         Part of profile(s): headset_head_unit   The problem here is not that the microphone does not work, but rather that the audio quality worsens when it is activated.


In an extreme low power project (MCU+BLE SIP running on a CR2016 battery for year(s)) I would like to measure the power consumption under different environments/algorithms.  What would be the correct way or setup to measure micro (nano ??) watts? in a short duration and over a long period of time?  The input voltage can be 3.2v - 1.7v (changes over time). I would like to eventually determine (or at least give a good estimation) to the duration a single battery would hold the device.

I need to sense the current of a target  through various periods of its on/sleep/off state and then need to send this data back to another interface MCU to read out the value. They will be both on the same board, powered by 5 V USB.  However these are the requirements I have:   5 V USB PSU Must be able to sense currents in the range of nA to mA with high    accuracy/precision. (I figure 1 nA to 500 mA) Only measure the current of the target MCU and not the interface. Must output maximum 3.3 V interface MCU   I have looked at available options and current sense amplifiers by Texas Instruments can't sense nA due to higher bias currents. So therefore I feel I would need a precision amplifier.  However I am stuck on how to proceed with this because, I need to somehow have a automatic dynamic current range and I am fairly new to current sensing and am not really sure on all the specifics.


I'm using PHP mail function to send a mail from HTML contact form.  HTML  <!DOCTYPE html>    <form id="newform" action="contact.php">   First name:
   <input type="text" name="firstname" value="Mickey">
   Last name:
   <input type="text" name="lastname" value="Mouse">

   <input type="submit" value="Submit"> </form>         If I just submit the form from JavaScript the mail goes to primary inbox and it is fine. But if I use the Ajax call to send the mail, the mail goes into spam folder. What could be the reason?  JavaScript for which mail goes to primary inbox  document.getElementById('form1').submit();   JavaScript for which mail goes to spam folder  $.post("contact_us.php", $("#form1").serialize(),  function(response) {            //DO something with response  });   PHP code  <?php       $subject = 'Hello People';  $from = "From: Hello <no-reply@hello.com>\r\n";   $to = 'hello@gmail.com';  $headers = "MIME-Version: 1.0\r\n";  $headers .= "Content-Type: text/html; charset=UTF-8\r\n";   $firstname = $_POST["firstname"]; $secName = $_POST["lastname"];    $message = '<form>

     First Name :   	     '. $firstname.'

     Last Name :   	     '.$secName.'

 </form>';    $result = mail($to, $subject, $message, $headers); if(!$result) {         echo "Error";    } else {     echo "Success"; }  ?>

This is a tricky one and I've always relied on techniques, such as permission-based emails (i.e. only sending to people you have permission to send to) and not using blatantly spamish terminology.  Of late, some of the emails I send out programmatically have started being shuffled into people's spam folder automatically and I'm wondering what I can do about it.  This is despite the fact that these particular emails are not ones that humans would mark as spam, specifically, they are emails that contain license keys that people have paid good money for, so I don't think they're going to consider them spam  I figure this is a big topic in which I am essentially an ignorant simpleton.


I am trying to install Ubuntu and it goes into the installer, but the only disk it sees is the usb drive. I shrank my primary partition in windows, so I have space ready. I disabled secure boot in Bios. Do I need something more?

I am trying to install Ubuntu 18.04 on my Dell XPS 15 9570.  I have followed the steps provided in the .  However, I have stumbled on an issue.   When I boot from USB I am immediately directed to the "Try Ubuntu" option. I do not manage to choose "Install Ubuntu"    I connect to WiFi here. And then open the Install Ubuntu 18.04 icon from the desktop.   I select the language and the keyboard   I then press "Continue" on the following window:  I get to the following window:    If I try to press "Install Now" it tells me:  When I try to press "change" or "+" the Install window closes.     I suspect the issue is that I need to change the drive to ACHI mode. But, I don't know why that would help and why can't it see the drive now.  I have create the bootable USB using Rufus 3.3 and then I have formatted it and tried again using UNetbootin. Same issue.


Where does 'pay through the nose' come from?

Where does the saying  " pay through the nose" originate?


I am reviewing for a test and i find the following good exercice. Would you please help me to prove the second part of the question b) here   for question a) i find $|G|=32$ since $G=C_8\ltimes C_2\times C_2$ Thanks for your help in advance.

Please help me to prove the following result:  I recall that the holomorph $Hol(\Gamma)$ of a group $\Gamma$ is the semidirect product $Hol(\Gamma)=\Gamma\ltimes_{\phi} Aut(\Gamma)$ where $\phi: Aut(\Gamma)\to  Aut(\Gamma)$ is the identity map.  Let $G=Hol(C_8)$. In addition let $f(x)\in \mathbb{Q}[x]$ be an irreducible polynomial of degree $8$, $L$ a splitting field of $f(x)$ over $\mathbb{Q}$ and suppose that $Gal(L/\mathbb{Q})\cong G$     Show that there is a subgroup of $S_8$ isomorphic to $G$   Thanks in advance.


I was looking on Howard Eves's book "An Introduction to the History of Mathematics" and I stumbled upon a demonstration on how $-1 = 1$. The demonstration follows:  $$ \sqrt{-1} = \sqrt{-1} $$  $$ \sqrt{-1\over1} = \sqrt{1\over-1}$$  $$ {\sqrt{-1}\over\sqrt{1}} = {\sqrt{1}\over\sqrt{-1}}$$  $$ \sqrt{-1}\cdot\sqrt{-1} = \sqrt{1}\cdot\sqrt{1} $$  Thus:  $$  -1 = 1  $$  My question is simple: how can it be? Where is the error? Is that a paradox?  Thanks in Advance!

I know there must be something unmathematical in the following but I don't know where it is: \begin{align} \sqrt{-1} &= i \\\\\ \frac1{\sqrt{-1}} &= \frac1i \\\\  \frac{\sqrt1}{\sqrt{-1}} &= \frac1i \\\\  \sqrt{\frac1{-1}} &= \frac1i \\\\  \sqrt{\frac{-1}1} &= \frac1i \\\\  \sqrt{-1} &= \frac1i \\\\  i &= \frac1i \\\\  i^2 &= 1 \\\\  -1 &= 1 \quad !!? \end{align}


I bought a new PicoScope USB oscilloscope and noticed that when I touch the tip of the probe with my hand I see a 50 Hz signal of 2 volts on the screen. What is causing this? (Or rather, how is the mains 50 Hz sine wave getting through me to the scope?)

Having no prior experience with scopes, it seems strange to me that when the probe is not measuring anything (~ not connected to a circuit) it measures a small 50Hz (~ my mains are running at 230V 50Hz) signal instead of some random noise. Is this normal behaviour (my scope is a Rigol DS1052E)?


I am using Safari 9.0.3 on OS X 10.11.9 and have only recently noticed Safari displaying the wrong favicon for some websites.  In one instance, Safari uses the Facebook icon for Messenger despite the Messenger icon being used in the head section of the page source.  I tried deleting the WebpageIcons.db file from Safari's Library folder, and I have cleared Safari history and website data across all my devices.  The Facebook icon still loads.  Any ideas?  Edit: To clarify, the proper Messenger.com icon appears in the bookmarks menu and the bookmarks editor window. However, the Facebook.com icon is used in the Smart Search Field.  Screenshot of Safari using the wrong favicon:   Facebook's Messenger.com icon:

I am using Safari on macOS Sierra. I have added several commonly-used sites to my favorites section, like so:    (there are 10 icons, and all but 2 of them are displayed as the proper, correct icon from the site. For example, the Wikipedia icon has the large W icon. However, for Google Drive and Gmail, the icons are just big, ugly, generic G's)  I would like for the two Google sites to correctly display their icons as well. At first, I thought it was because all 8 of the "correctly displayed" sites had successfully configured their "Safari settings" or something like that, while Google failed to do this (although this doesn't sound too plausible).  However, if I instead go to the top menu in Safari, click Bookmarks > Show Bookmarks, I get the following:    Strangely, this time, the two Google sites do have correctly displayed icons, while it is instead three other sites (out of the 10) that aren't displayed: namely Wikipedia, Amazon, and New York Times.  So it seems that there are two sets of icons, "big" and "small", and for big icons, Google Drive and Gmail are not displayed correctly, while the other 8 are, and on the other hand, for small icons, Google Drive and Gmail are displayed correctly, while Wikipedia, Amazon, and NYTimes are not.  I actually don't care too much about the small icons, but I would really like for all the big icons to display correctly. How can I do that?


I want a debugging output function to contain a test: if the object has a toString function, use it.  But then, every JavaScript object has a toString function, so what I really want is to check whether it has been assigned toString instead of just inheriting a default one.  What's the best way to do this? It occurs to me maybe you could exploit the fact that the inherited function isn't visible in for-in iteration, though it feels like there ought to be an O(1) solution.

How do I check if an object has a specific property in JavaScript?  Consider:  x = {'key': 1}; if ( x.hasOwnProperty('key') ) {     //Do this }   Is that the best way to do it?


I have yet to see this, but was wondering if others have or if it makes sense to list acknowledgments in published papers on a CV.  In some questions on this SE, it seems significant contributions to a paper can occur, yet for some reason (maybe not contributing to writing of the paper), the person is listed in acknowledgments and not co-author.  This seems like something that is of relevance/importance.  In the other case, acknowledgments can be 'thanks for the discussion' in which it may have been a brief conversation with one important realization through the talk.  This seems more like daily life.   Some people seem to list their contributions tot he academic community, such as being a reviewer for a journal.    What would you think if you saw acknowledgments on a CV, or, would it make more sense to categorize acknowledgments into other topics, such as, 'Non-co-authored project participation'.

Suppose that I've helped other researchers with the statistical analyses for an epidemiological study and therefore I am acknowledged for that in the "Acknowledgments" section of the paper (something like "We thank andrea for his statistical support").  Obviously, this doesn't count as a publication for me, as I am not one of the authors. But if I include it in my CV, how much "weight" would a professor (or someone within the academia) give to that? I also have other publications where I am either the first author or one of the co-authors.  I am not thinking of a particular situation here (like applying for a grant or for a PhD position). I am just curious to know if it could be useful to put it into my CV or if it would just be irrelevant.


I've got a Samsung / Google Nexus 10 tablet, and I'd like to find a way to use my AudioTechnica AT2020 USB condenser microphone with it. The microphone has a standard USB type B connector on it (similar to a printer), and the typical cable goes to a USB type A connector.  Does anyone know if there is any way to hook this up, so I can record audio with my tablet?

Blue makes  that you can connect directly to an iPod or iPhone via the dock port. I would love to have the same capability to do something similar for an Android phone or tablet. This would be really useful for field recording. I know that some tablets have support for various USB accessories to be plugged in, but I don't know if the OS can handle a microphone. Is this possible using existing or near future (Ice Cream Sandwich) hardware/OS combinations?


\documentclass[oneside]{book}    \usepackage{geometry}% For the margins.   \usepackage{lipsum}   \newgeometry{       top=1in,       bottom=1in,       outer=1in,       inner=1in,   }  \usepackage{setspace}%Spacing between entries in array.   \doublespacing% Self explanatory.   \usepackage[justification=centering]{caption}   %\setlength{\textfloatsep}{-10pt}   \usepackage[toc,page]{appendix}%for the appendix   \usepackage{amsmath,amsthm,amssymb,amsfonts}   \usepackage{pgf,tikz}%plots,pics, drawings, etc.   \usepackage{tikz-3dplot}%For 3-D plots   \usepackage{mathrsfs}% For fancy "F"   \usetikzlibrary{arrows}   \usepackage{float}   %\usepackage{tikzpicture}   \usepackage{mathtools}   \usepackage{gensymb}% for degree symbol.   %\usepackage{pgfplots}%For coordinate plane   %\usetikzlibrary{calc,angles,positioning,intersections,quotes,decorations.markings,backgrounds,patterns}   \usepackage{cancel}   \usepackage{color}   \usepackage{polynom}   \usepackage{graphicx}   \usepackage{fouriernc}   \usepackage[T1]{fontenc}   \usepackage{fancyhdr}%Shorten Section/Chapter titles in the headers of pages.   \pagestyle{fancy}   \usepackage{listing}   \usepackage{qtree}% For drawing trees.   \usepackage{pstricks,pst-node,pst-tree,pstricks-add}%This might be better.df   \setlength{\parskip}{1em}%Space between paragraphs.    \usepackage{multicol}  \begin{document} \begin{figure}[h]   \begin{center}%\centering   \begin{tikzpicture}[line cap=round,line join=round,>=triangle   45,x=1.0cm,y=1.0cm, scale=1]%line cap=round,line join=round,>=triangle   45,x=1.0cm,y=1.0cm, scale=1   \clip(-4,-1.6) rectangle (5.5,1.6);   \draw [line width=0.35mm, loosely  dotted] (0.,0.)-- (2.,0.);   \draw [line width=0.35mm] (0.,0.)-- (1.,1.);   \draw [line width=0.35mm] (0.,0.)-- (1.,-1.);   \draw [line width=0.35mm, loosely dotted] (1.,1.)-- (2.,0.);   \draw [line width=0.35mm] (1.,-1.)-- (2.,0.);   \draw [line width=0.35mm] (2.,0.)-- (3.,1.);   \draw [line width=0.35mm, loosely dotted] (2.,0.)-- (3.,-1.);   \draw [line width=0.35mm] (2.,0.)-- (4.,0.);   \draw [line width=0.35mm] (3.,1.)-- (4.,0.);   \draw [line width=0.35mm, loosely dotted] (3.,-1.)-- (4.,0.);   \begin{scriptsize}   \draw [fill=black] (0.,0.) circle (2pt) node[yshift=0.4cm] {\large A};   \draw[fill=black] (1,1) circle (2pt) node[yshift=0.4cm] {\large B};   \draw[fill=black] (1,-1) circle (2pt) node[yshift=-0.4cm] {\large C};   \draw [fill=black] (2.,0.) circle (2pt) node[yshift=0.4cm] {\large D};   \draw [fill=black] (4.,0.) circle (2pt) node[yshift=0.4cm] {\large E};   \draw[fill=black] (3,-1) circle (2pt) node[yshift=-0.4cm] {\large F};   \draw[fill=black] (3,1) circle (2pt) node[yshift=0.4cm] {\large G};   \end{scriptsize}   \end{tikzpicture}   \caption{Example of a graph with open and closed edges.} \label{1}   \end{center}   \end{figure} \end{document}     What do I need to do so that my figure that I got from GeoGebra is centered in my paper?

I want to put this figure (Matrix) at the center but I can't, even though the title is centered:    How to do this please?  I have this code :  \begin{center} \begin{figure}[H]         \begin{center}                     \[                     \begin{blockarray}{cccccc}                     123 & 12,3 & 13,2 & 1,23 & 1,2,3\\                     \begin{block}{(ccccc)c}                       0 & 1 & 1 & 1 & 0 & 123 \\                       1 & 0 & 0 & 0 & 1 & 12,3 \\                       1 & 0 & 0 & 0 & 1 & 13,2 \\                       1 & 0 & 0 & 0 & 1 & 1,23 \\                       0 & 1 & 1 & 1 & 0 & 1,2,3 \\                     \end{block}                     \end{blockarray}                     \]         \end{center}   \caption{ Matrice d'adjacence de treillis de 5 partitions de $E = \{1,2,3\}$} \end{figure} \end{center}


I am trying to learn all I can about the cat command. I am going to be using it for its light weight performance and its ability to work in nothing but a command line.  I know it can create a text file and read it with quite a few perks but I cant figure out how to edit an already existing one.  There is a similar question to this (What is 'cat' used for?) but it doesn't say were the limits are for the cat command.      If anyone has any advice or know some good sources to learn this stuff from I would greatly appreciate it.  Thank you.

I've seen the cat command come up in some online stuff and I was curious as to what cat did and what it's for in the context of someone who is just doing some simple command line stuff.


How many rings of order 4 can exist upto isomorphism   there are only two groups $Z_4$ and $K_4$ upto isomorphism where $Z_4$ is abelian and $K_4$ is non-abelian.To be a ring that must be a abelian group under one binary operation.Can it be say that $Z_4$ is only ring of order 4 upto isomorphism

Is the following statement is true?     There are at least three mutually non-isomorphic rings with $4$ elements.   I have no idea or counterexample at the moment. Please help. So far I know about that a group of order $4$ is abelian and there are two non isomorphic groups of order $4$ like $K_4(non cyclic)$ and $\mathbb Z_4(cyclic)$.


I remember a quote from a while ago that went somewhere along the line x is saying ´fuck you´ to a person but making them feel flattered   It's a quality that makes somebody polite, manipulative and tactful.

Is there a specific term for a statement that uses words such that their precise meaning conveys a subtext contrary to the colloquial meaning?  For example, the joke in Men in Black:     Gentlemen, congratulations. You're everything we've come to expect   from years of government training.   where the precise use of the words conveys a sarcastic meaning (ie that the candidates are inept because that's what he's come to expect from government training).  I was going to use "irony" to describe this but then realized this is basically the opposite of irony - the use of words to convey their literal intention, when a nonliteral intention was expected.


When I try to compile my paper I get the following error:  ! LaTeX Error: Filemathtools.sty' not found.`  Other packages are successfully found and automatically installed, but mathtools.sty is not. I just reinstalled windows 8.1 and Miktex 2.9 with TeXWorks Version 0.4.5. The paper compiles properly on my other machines.  I have found mathtools.sty online, but adding it manually only results in another style file not being found. What is going on - why is Miktex failing to automagically find mathtools.sty and other style files?  EDIT The problem is that the package manager has somehow "desynchronized" (even though it's a fresh install). To fix it, run Miktex Package Manager as administrator---there should be a version "Package Manager" and a version "Package Manager (Admin)" - run the latter. Go to Repository-->Synchronize. When that completes, close the package manager and your TexWorks should automatically find the needed style files again. If the synchronize fails, then you may not have run the (Admin) version of Package Manager.

There have been a few questions regarding installing this package in the past, but they now seem to be out of date. I'm using MiKTeX 2.9 and TexMaker. When I try \usepackage{mathtools} in TexMaker it will try to install the package for me but will fail. I took the advice given in this thread:   As suggested I tried installing the mh package using the MiKTeX Package Manager, unfortunately I get the "unknown archive size" error, which I have read means that the package no longer exists. Another thread (lost the link) said you can use the MiKTeX Package Manager to directly install mathtools, however I do not see mathtools listed anywhere in the MiKTeX Package Manager...   So I ask, is the package under a different name? Are there any other ways to install this package?


I have a PHP array being created from a .csv file, the resulting array has data that I have no use for so I would like to cleanup the array before proceeding.  array (size=45)   0 =>      array (size=63)       '"Unique ID"' => string '3585370' (length=7)       'Source ID' => string '242' (length=3)       'Source Date' => string '20/9/18 12:08:22 AM' (length=19)       'Email' => string 'email@email.com' (length=3)   How can I remove "Source Date" and "Source ID" from the array of each record?

Is there an easy way to delete an element from an array using PHP, such that foreach ($array) no longer includes that element?  I thought that setting it to null would do it, but apparently it does not work.


How do you do. My old website was based on uCoz. It was desined badly and was based on uCoz free domain. I decided to create the new site version myself, going to another hosting and changing the design. But the old website had got some good articles. I've heard that search engines will be able to decide that the articles were stolen if I just copy them. I don't want to use rewriting. Is it posible to move them without a risk for SEO? Excuse my English.

I'm using the Yoast SEO plugin on a WordPress site on a new, more memorable domain to replace an old static HTML site with no SEO. I've followed , set up 301 redirects from the old domain to the new one, and filed a change of address in the Google Search Console. However, after a few days, the old site still shows in search results, and is ranked higher than the new one if you google our company name.   And, if I try to set the preferred domain in the Google Search Console Site Settings for the new site, I see this in place of the options to prefer www/non-www/http/https:     Not all options are available because of a Change of Address request   related to this site.   I've read of some cases where this condition has lasted for .  Is there anything more I can do to fix this? Have I done something wrong, or do I just need to wait, and for how long?


I am stuck with this question and a reasonable answer will be well appreciated.  Suppose a numerical data is obtained from the same people by two different investigators. However, we could not link the people, so the pairing is unknown. In addition, nor the investigators could get a hold of all people. For example, investigator 1 could take the measurement of 100 people whereas investigator 2 had it for 79 people. So there are some missing observations. Can I do an independent t-test with these two samples? Thank you in advance!

The study I am analysing is a pre-and-post intervention questionnaire of students' views before and after studying a module.  The questionnaire was distributed in three different geographical locations, where the same instructor was delivering the same module at different times within one year.  The scale used is a 5-point Likert scale (which I can also convert into a binary agree/disagree variable if needed).   The surveys are anonymous, so I can't match the sample.  However, in some samples, all the students answered both the pre-and-post questionnaires (same $N$) and in others this was different (different $N$).   Overall I have 343 respondents for the pre-intervention questionnaire, and 378 respondents for the post-intervention questionnaire.  However in two of the three locations, I have equal pre and post intervention responses, but they are anonymous: so they are not independent, but not matched. (This is a weakness of the data, and will be reported in the results).  My questions are: a) Given the sample size, would running an unpaired t-test on the full sample be appropriate? Or should I be going for a non-parametric test?  b) Can the subsamples where there are equal respondents (i.e. all students answered both pre-and-post questionnaires) be analysed as non-independent non-matched samples?


If \$\rm{Re}( Z)\$ gives the reactance of a circuit, then what is the physical meaning of \$|Z|\$? How do they differ, and when would one use one over the other? (Where \$Z\$ is the impedance of an arbitrary circuit)

What is the difference between the Resistance and Impedance? When we will say it is an Impedance and when we will say it as an Resistance? Can you explain it with diagram (If possible) and real time example.    And how the reactances will form in the circut where the Capacitors and inductors are not available in our circuit? How we will find the reactances in the circuit and its values in real time?   I means is this possible to calculate the reactance by using any instrument? Do the reactance was intentionally kept by the designer or generally it'll forms with in the circuit?   All answers are appreciated.


It didn't fit in the title, but I'm talking about questions answered by others, i.e. not self-answered . On some SE sites (e.g. politics, if I recall correctly) one cannot delete his own question that has been answered by others, while on other SE sites (e.g. on psychology) such an action is possible. Why this difference? Is there a site-wide flag controlling this behavior?

What circumstances can cause a question or answer to be deleted, and what does that actually mean?    How can a post be deleted? When can't I delete my own post? Can I still see my post even after it's deleted? Can I see a list of my deleted posts? How can I undelete one of my posts? What does deletion mean for a post? How do votes to delete work? What are the criteria for deletion? What else should I know about deleted posts? If I flag my question with a request to delete it, what will happen?       For more information, see the articles about  and  in the .


Currently I'm learning about C and OpenMP. I wrote the following program: #include <omp.h> #include <stdio.h> #include <stdlib.h> #define N 960  int main (int argc, char *argv[])  {     int nthreads, tid, i, j;     double a[N][N];  /* Fork a team of threads */     #pragma omp parallel shared(nthreads) private(i,tid,a)     {         tid = omp_get_thread_num();         if (tid == 0)          {             nthreads = omp_get_num_threads();             printf("Number of threads = %d\n", nthreads);                      }         printf("Thread %d starting...\n", tid);                  #pragma omp for         for (i=0; i<N; i++)         {             for (j=0; j<N; j++)             {                 a[i][j] = tid + i + j;             }                      }     } }  When I compile the code it compiles. I use in a Linux terminal: gcc name.c -o name -lm -fopenmp  When I want to excecute the program I get a segmentation error. I searched for a definition: A segmentation fault occurs when a program attempts to access a memory location that it is not allowed to access, or attempts to access a memory location in a way that is not allowed I don't really see how I try to access a memory that is not allowed. Could I please get feedback on why I get a segmentation error?

The following code is generating a stack overflow error for me  int main(int argc, char* argv[]) {     int sieve[2000000];     return 0; }   How do I get around this? I am using Turbo C++ but would like to keep my code in C  EDIT:  Thanks for the advice.  The code above was only for example, I actually declare the array in a function and not in sub main.  Also, I needed the array to be initialized to zeros, so when I googled malloc, I discovered that calloc was perfect for my purposes.  Malloc/calloc also has the advantage over allocating on the stack of allowing me to declare the size using a variable.


If I were to have all four games, could the pokedex be completed? Excluding the event mons, of course.

I just bought Pokemon Alpha Sapphire for myself and Omega Ruby for my friend. I also played the X/Y games and I have Pokebank. The problem is: I didn't play games of the 5th and 4th generation. I basically skipped the Nintendo DS games and started playing again with the release of Pokemon X/Y.  My question is: Is it possible to complete the Pokedex with only the four 6th Gen games (X, Y, Omega Ruby, Alpha Sapphire)? Or will there be some unobtainable Pokemon?   I'm not talking about the rare legendary ones like Celebi, Arceus etc. I just want to know whether I need to use a 5th gen game or not to "Catch 'Em All".


Does the Wubi allow you to create a proper ext4 partition and install Ubuntu? Or is it that the Wubi will only allow me to install it in the C partition?

At this time, Wubi does not work with Windows 8 default boot-loader. Thus at this point Wubi would not work on a new Windows 8 machine.      Citation fom    Question  Recently I've learned of , a way to install Ubuntu right from Windows.  Besides installing from Windows, I would like to know key differences between a regular "alongside Windows" or Dual-boot Ubuntu installation and one done with Wubi. Are there any disadvantages (for example a performance penalty) or incompatibilities I should look out for when using Wubi?


I recall that there was a Putnam problem which went something like this:  Find all real functions satisfying  $$f(s^2+f(t)) = t+f(s)^2$$  for all $s,t \in \mathbb{R}$.  There was a cool trick to solving it that I wanted to remember. But I don't know which test it was from and google isn't much help for searching with equations.  Does anyone know which problem I am thinking of so I can look up that trick?

Let $\mathbb R$ denote the set of all real numbers. Find all function $f: R\to \ R$ such that   $$f\left(x^2+f(y)\right)=y+(f(x))^2$$   It is the problem. I tried to it by putting many at the place of $x$ and $y$ but I can't proceed. Please somebody help me.


I have an Lenovo Ideapad S10-2 Like this  Processor / Chipset CPU Intel Atom N270 / 1.6 GHz  Cache L2 cache - 512.0 KB  Front Side Bus 533.0 MHz  Chipset Mobile Intel 945GSE Express  Features Hyper-Threading Technology  RAM 2.0 GB DDR2 SDRAM 533.0 MHz / PC2-5300  Form Factor SO DIMM 200-pin   Audio & Video Graphics Processor Intel GMA 950  Memory Allocation Technology Dynamic Video Memory Technology 3.0   Which ubuntu derivative should i use for best driver and device performans compatibility  im a general purpose user frequently surf on internet, sometimes i need remote desktop connection, office extension document files, and video multimedia files.  Your suggestions are very important for me because windows slow down my system heaps of times.. so i want to use ubuntu anymore.  Thanks in advance, Best Regards

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


The box has the same weight. I think that the stairs does more work because it travels a further distance as it is a less direct path opposed to going straight up.

This might be a stupid question, but why exactly is work a path function?  In school, my teacher said it’s because it depends on the path. She gave an example of walking up a mountain, and said the work you expend depends on the path you take (straight path up or circling up around the mountain). But isn’t the work expended just equal to $E= mgh?$


Just upgraded from Windows 7 to Windows 10.  Found the lack of colored window titlebars to be quite annoying (Chrome, in particular, looked absurd with a white titlebar background), but was able to fix that by follow .  The next issue is that the titlebars are no longer transparent as they used to be under Windows 7.  I'd like to turn the transparency back on, and there seem to be various news posts scattered about that imply that Microsoft decided to .  However I'm not having any luck finding out where this setting is, or if it even exists.  It seems like it may have only been enabled for the start menu?  Is there a way to make the window titlebars non-opaque in Windows 10, and if so, how?

I've updated from Windows 7 to Windows 10 and I miss the Aero Glass transparency that I had in Windows 7.   How can I enable this again?


We have two eigenvalues $\lambda_1$ and $\lambda_2$, with $\lambda_1 = \lambda_2 < 0$. Consider the case we have only one linearly independent eigenvector. Then the phase portrait is a (stable) degenerate node. I have seen two different phase portraits for this case:    In general, how we decide which phase portrait we need?

I have a question with respect to phase plots of repeated eigenvalue cases. For instance suppose that one is given a matrix with the following:   $$\overrightarrow{y'} = \begin{pmatrix} 3 & -4 \\ 1 & -1  \end{pmatrix} \overrightarrow{y}$$  whereby the solution yields:   $$\overrightarrow{y} = c_1e^t\binom{2}1 + c_2(te^t\binom{2}1 + e^t\binom{1}0)$$  I understand that it is asymptotically unstable but what I am unclear is the direction and whether one should plot it according to the following two figures      How does one distinguish which way the curves come out of the origin from just from analyzing the system ? I am aware that the plot should actually be the 2nd picture but I am not sure why so some help with respect to this technique would be appreciated.


I've installed Ubuntu Tweak on Ubuntu 14.04 and I can only run it by going to the terminal and typing ubuntu-tweak.  There's no icon in the drop down menu. I installed GNOME flashback so I am just trying to get a launcher icon somewhere in the launcher. It's not in system settings either.

I have heard a lot about Ubuntu-Tweak and how it is great for power users, but I don't know how to install it.  How do I do that?


Hi all, I am following a one point tracking tutorial on youtube and everything worked fine until the compositing stage. I am having trouble showing the Renter layers on the movie. Is there anything i missed? Please help!  Best Regards, Gary

Is there a way to use nodes to combine two images if both the images have transparency (i.e. alpha channels)?


Suppose 500 individuals were asked one question having possible answers ”yes” or “no”. Denote by p the proportion of “yes” in the whole population. Estimate the probability that the proportion of “yes” in the sample (out of 500) is greater than in the whole population (p) by more than 5 %.  I was thinking of using the normal approx of the binomial where.. n = 500 p = 0.5 q = 0.5       Formula: \begin{align*}  P\left(\frac{N - np}{\sqrt{npq}}\right)\\ \end{align*} However, I'm not sure what the N value would be in this case.

Suppose $53$ percent of the population prefer red socks to green. If $100$ random people are asked, what is the probability that most (at least $50$) will say prefer GREEN:  So I set \begin{align*} N & = 49.5\\   n & = 100\\   p & = 0.47 \end{align*}  Then.. \begin{align*}    P(N \geq 49.5) & = P\left(\frac{N - np}{\sqrt{npq}}\right)\\                & \geq \frac{49.5 - 47}{\sqrt{100*.47*.53}}\\                   & = \varphi(0.50)\\                   & = 0.3085   \end{align*} Except, that's not the right answer. What did I do wrong in my calculations?


I am attempting to store a string in a variable declared as char *name[2];. I am using scanf() to obtain the value from user input. This is my code so far and its currently not working:  #include <stdio.h> #include <stdlib.h> int main() {   char *name[2];     scanf("%s",name[0]);     printf("%s",name[0]);     return 0; }

The following code receives seg fault on line 2:  char *str = "string"; str[0] = 'z';  // could be also written as *str = 'z' printf("%s\n", str);   While this works perfectly well:  char str[] = "string"; str[0] = 'z'; printf("%s\n", str);   Tested with MSVC and GCC.


I'm trying to prove by induction that for all $a,b \in \mathbb{Z}$ and $n \in \mathbb{N}$, that $(a-b) \mid (a^n-b^n)$. The base case was trivial, so I started by assuming that $(a-b) \mid (a^n-b^n)$. But I found that: \begin{align*} (a-b)(a^{n-1}+a^{n-2}b + a^{n-3}b^2+...+b^{n-1}) &= a^n-b^n. \end{align*}  Doesn't this imply that $(a-b) \mid (a^n-b^n)$ as $a^{n-1}+a^{n-2}b+\dots+b^{n-1}$ is clearly an integer? This obviously isn't a proof by induction, but is there anything wrong with taking this approach to prove this result, other than the fact that it isn't what is being asked?   Aside, I'm having trouble getting started with the proof by induction. I've tried making the above equivalence useful during the induction step, but it doesn't seem to be helpful, so any hints would be greatly appreciated!

I did some mathematical induction problems on divisibility   $9^n$ $-$ $2^n$ is divisible by 7. $4^n$ $-$ $1$ is divisible by 3. $9^n$ $-$ $4^n$ is divisible by 5.   Can these be generalized as $a^n$ $-$ $b^n$$ = (a-b)N$, where N is an integer? But why is $a^n$ $-$ $b^n$$ = (a-b)N$ ?  I also see that $6^n$ $- 5n + 4$ is divisible by $5$ which is $6-5+4$ and $7^n$$+3n + 8$ is divisible by $9$ which is $7+3+8=18=9\cdot2$.  Are they just a coincidence or is there a theory behind?  Is it about modular arithmetic?


I create a view (eg Generic) which defaults to a mini pager 10 items.  When I visualize this view, I would like to dynamically change the number of items in the passing 3.  How? What hook to use?

I create a view (FO) that lists certain content type. By default, I put a pager (mini) and a number of items per page (content 10 per page).  This view, I integrated into a content type (CFTO) in addition to other parameters. If I agree, I want to use my other variables to redefine this view without saving it in a database (eg disable the pager / display 3 content page / ...)  I try different hooks as hook_views_pre_view, hook_views_pre_render, views_pre_build, but nothing works. I can not change the number of a content page. This is my different test :   I wish i could change my view different information as enable / disable pager and more then change the number of elements of the page.  I find a way of hook_views_pre_render(&$views) to change the pager and more. It works well.  function my_views_pre_render(&$view){ //For more $view->display['page']->handler->options['use_more'] = TRUE;  //For pager if(!$this_node_pager_value) {     $view->query->pager->set_items_per_page($view->total_rows);     $view->query->pager->update_page_info(); }}   Now i wish i could change the number of elements in my page to display, I tested this code in different hook sities previously.  function my_views_pre_render(&$view){ if($this_node_pager_value) { //TEST 1 $view->query->pager->set_items_per_page(3); $view->query->pager->update_page_info();  //TEST 2 $view->exposed_raw_input['items_per_page'] = 3; }}  function my_views_pre_view(&$view, &$display_id, &$args){ //TEST 1 $view->display_handler->display->display_options['pager']['options']['items_per_page'] = 3;  //TEST 2 $view->query->pager->set_items_per_page(3); $view->query->pager->update_page_info();  //TEST 3 $view->exposed_raw_input['items_per_page'] = 3;  }  function my_views_pre_execute(&$view){ //TEST 1 $view->display_handler->display->display_options['pager']['options']['items_per_page'] = 3; //TEST 2 $view->query->pager->set_items_per_page(3); $view->query->pager->update_page_info(); //TEST 3 $view->exposed_raw_input['items_per_page'] = 3; //TEST 4 $view->display_handler->set_option('items_per_page', 3); }   function cci_generic_views_pre_build(&$view){ //TEST 1 $view->pager["items_per_page"] = 3; //TEST 2 $view->display_handler->options['pager']['options']['items_per_page'] = 2; //TEST 3 $view->display_handler->options['pager']['options']['expose']['items_per_page'] = 2; }   None works. Would you know what should be done to make it work?  You would know what is the right hook to use? And how to change this value? thank you for your help   Djik


I'm new in LaTex. I need to draw a graphic like the image and each rectangles of image must have the size shown in Figure. I drawn it by MS power point but I need to do by LaTex. Can you help me? Or how to start? Thank you in advance for your help and collaboration!   Now I'm able to generate the box by this code  \documentclass[border=10pt]{standalone} \usepackage{tikz} \usetikzlibrary{calc,shapes.arrows} \usetikzlibrary{automata} % LATEX and plain TEX \usetikzlibrary{arrows,decorations.pathmorphing,backgrounds, chains,positioning,fit,petri,matrix,shapes.arrows,shadows,backgrounds}  \usetikzlibrary{mindmap}    \usetikzlibrary{shapes,arrows,fit,calc,shadings,graphs} \tikzset{box/.style={draw, rectangle, rounded corners, thick,node distance=7em, text width=6em, text centered , inimum height=3.5em}} \tikzset{container/.style={draw, rectangle , dashed, inner sep=2em}} \tikzset{line/.style={draw, thick, -latex '}}   %Disegno per i grafici TikZ \definecolor{bluei}{RGB}{83,116,191} \definecolor{blueii}{RGB}{207,212,232} \definecolor{greeni}{RGB}{135,200,81} \definecolor{greenii}{RGB}{216,235,207}  \tikzset{   myiblock/.style 2 args={     draw=white,     fill=#1,     line width=1pt,     rounded corners,     minimum height=1cm,     align=center,     text=white,     font=\sffamily,     text width=#2   },   myoblock/.style={     fill=#1,     rounded corners,     align=center,     inner xsep=10pt   } }  \begin{document}   %1chain  \begin{tikzpicture}[node distance=3pt and 1cm] \node[myiblock={bluei}{2cm}]   (info1)   {Id1 long 7 chars}; \node[myiblock={bluei}{2cm},below=of info1]   (info2)   {Id2 long 7 chars};  \node[myiblock={bluei}{2cm},below=of info2]   (info3)   {Id3 long 7 chars};   \node[myiblock={bluei}{2cm},below=of info3]   (info4)   {Id4 long 7 chars};     \node[myiblock={bluei}{2cm},below=of info4]   (info5)   {Id5 long 7 chars};     \node[myiblock={bluei}{2cm},below=of info5]   (info6)   {Id6 long 7 chars};     \node[myiblock={bluei}{2cm},below=of info6]   (info7)   {Id7 long 7 chars};   \begin{pgfonlayer}{background}  \end{pgfonlayer}  %2 chain  \begin{scope}[xshift=6cm,node distance=3pt and 1cm] \node[myiblock={greeni}{4cm}]   (infoob1)   {Text1 long 34 chars}; \node[myiblock={greeni}{4cm},below=of infoob1]   (infoob2)   {Text2 long 34 chars}; \node[myiblock={greeni}{4cm},below=of infoob2]   (infoob3)   {Text3 long 34 chars};  \node[myiblock={greeni}{4cm},below=of infoob3]   (infoob4)   {Text4 long 34 chars};   \node[myiblock={greeni}{4cm},below=of infoob4]   (infoob5)   {Text5 long 34 chars};   \node[myiblock={greeni}{4cm},below=of infoob5]   (infoob6)   {Text6 long 34 chars};   \node[myiblock={greeni}{4cm},below=of infoob6]   (infoob7)   {Text7 long 34 chars}; \begin{pgfonlayer}{background} \end{pgfonlayer} \end{scope} \end{tikzpicture}  %3 chain  \begin{tikzpicture}[node distance=3pt and 1cm] \node[myiblock={bluei}{2cm}]   (info1)   {Label1 long 20 chars}; \node[myiblock={bluei}{2cm},below=of info1]   (info2)   {Label2 long 20 chars};  \node[myiblock={bluei}{2cm},below=of info2]   (info3)   {Label3 long 20 chars};   \node[myiblock={bluei}{2cm},below=of info3]   (info4)   {Label4 long 20 chars};     \node[myiblock={bluei}{2cm},below=of info4]   (info5)   {Label5 long 20 chars};     \node[myiblock={bluei}{2cm},below=of info5]   (info6)   {Label6 long 20 chars};     \node[myiblock={bluei}{2cm},below=of info6]   (info7)   {Label7 long 20 chars};   \begin{pgfonlayer}{background}  \end{pgfonlayer} \end{tikzpicture}  \end{document}   question: 1. how i can add the other box 2. how to add the ...between the box (see the first chain) 3. how to keep the same box size of the original image?  Thanks Marta

I'm new in LaTex. I need to draw a graphic like the image and each rectangles of image must have the size shown in Figure. I drwan it by MS power point but I need to do by LaTex. Can you help me? Thank you in advance for your help and collaboration!  Thank you in advance for your help and collaboration!