Hi guys just wondering if anyone could give me some assistance. Trying to make a python script to control a greenhouse with a raspberry pi, still in early stages at the moment.   Problem is i need a certain section of code to loop so it continually keeps the correct temp, etc i want this to occur as long as a variable is equal to 1 this is controlled by a GUI button (and works fine). Just as a test i got the code to print the temprature (value) from the slider but when its changed the Tkinter window crashes (Not Responding). Anyone know the reason or have a fix.  Entire Code:#  from tkinter import * root = Tk() import time  #--------------------VARIABLES--------------------# ManOverideToggleINT = 0 AUTOMODETOGGLESTATEINT = 0 #------------------TKINTER SETUP------------------# root.title("GREENHOUSE CONTROL - GUI") root.geometry('800x480') #root.attributes('-fullscreen', True) #MAKE IT FULL SCREEN UN-COMMENT WHEN CODE DONE   #---------------CONTROLS AUTO MODE----------------# """ This function will control the greenhouse when manual overide in not engaged (==1), monitor temp, humidity, etc.  MORE RESEARCH NEEDED ON PLANTS NEEDS """ def AUTO():     global AUTOMODETOGGLESTATEINT     while AUTOMODETOGGLESTATEINT == 0:         print(CONSTEMP.get())         time.sleep(5)         """ ############## GPIO PINS NEEDED INPUTS/OUTPUTS ##############          COOLING IF TOO WARM          if (realtemp>CONSTEMP.get()):             print("Cooling activated" + realtemp + " > " CONSTEMP.get() + " (desired)")         COOLING OFF IF TOO WARM          elif (realtemp<CONSTEMP.get()):             print("Cooling deactivted" + realtemp + " < " CONSTEMP.get() + " (desired)")         """         print("AUTO LOOP HERE") #--------------CONTROLS MANUAL MODE---------------# """ Manual mode will allows the user to specify specific conditions inside the green house """ def MANUAL():     global AUTOMODETOGGLESTATEINT     if AUTOMODETOGGLESTATEINT == 1:         print("AUTO REGULATION HAS BEEN TURNED OFF")         print("LOOP UNTILL BACK ON")  #def ToggleWait():   def AUTOMODETOGGLE():     global AUTOMODETOGGLESTATEINT     if AUTOMODETOGGLESTATEINT == 0:         print("Auto Mode OFF")         TOGGLE["text"] = "AUTO REGULATION = OFF"         AUTOMODETOGGLESTATEINT = 1         MANUAL()     else:         print("AUTO REGULATION = ON")         TOGGLE["text"] = "AUTO REGULATION = ON"         AUTOMODETOGGLESTATEINT = 0         AUTO()   TOGGLE = Button(root, text="AUTO REGULATION = ON", command=AUTOMODETOGGLE) TOGGLE.pack() CONSTEMP = Scale(root, orient=HORIZONTAL, length=300, width=50,from_=10,to=40,tickinterval=5,)#25c is optinum CONSTEMP.pack()  root.mainloop()

My little brother is just getting into programming, and for his Science Fair project, he's doing a simulation of a flock of birds in the sky. He's gotten most of his code written, and it works nicely, but the birds need to move every moment.  Tkinter, however, hogs the time for its own event loop, and so his code won't run. Doing root.mainloop() runs, runs, and keeps running, and the only thing it runs is the event handlers.  Is there a way to have his code run alongside the mainloop (without multithreading, it's confusing and this should be kept simple), and if so, what is it?  Right now, he came up with an ugly hack, tying his move() function to <b1-motion>, so that as long as he holds the button down and wiggles the mouse, it works. But there's got to be a better way.


Is energy fundamentally the will of the universe?

The simplistic undergrad explanation aside, I've never really understood what energy really is. I've been told that it's something when converted from one kind of something to another kind, or does some "work", as defined by us, but what is that something?  Moreover, if the total amount of energy in the universe is finite and we cannot create energy. Then, where did it come from? I've learned from thermodynamics where it goes, but where does it come from?  I know this sounds like something trivially simple, but there is so much going on in the physical universe and I just can't grasp what it is. Maybe it is because I lack the mathematical understanding that I can't grasp the subtle things the universe is doing. Still, I want to understand what it is doing.  How do I get to the point of understanding what it's doing?  (Note: What prompted me to ask this was . I'm afraid that it just puzzled me further and I sat there staring at the screen for a good 10 minutes.)


I'm using biblatex with natbib enabled. I would like to insert some text into multiple citations using \citetext as:  \citetext{\citep{Ginsburg:1988ie}; but see \citep{Allik:1991ft}}    which gives me:     ([Ginsburg & Nicholls, 1988]; but see [Allik, Tuulmets, & Vos, 1991])   However, I would like square brackets deleted. Anyone help?

Using BibLatex with the apa style I try to cite some references in the following way:     ... slightly adapted Biggs’ (1987, 1999; see for a similar model Marsick, Watkins, & O’Conner, 2011) model of ...   I tried to get the result as following (MWE)   \documentclass[a4paper,10pt]{article} \usepackage[utf8]{inputenc} \usepackage[style=apa, backend=biber, sortcites=true]{biblatex}  \usepackage{filecontents}  \begin{filecontents}{\jobname.bib} @book{biggs1987,     location = {Melbourne},     title = {Student approaches to learning and studying},     publisher = {Australian Council for Educational Research},     author = {Biggs, J.},     date = {1987} }  @book{biggs1999,     location = {Buckingham},     title = {Teaching for quality learning at university. What the student does},     publisher = {Society for Research into Higher Education},     author = {Biggs, J.},     date = {1999} }  @incollection{marsick2011,     location = {London},     title = {Researching workplace learning in the United States},     pages = {198--209},     booktitle = {The international handbook of workplace learning},     publisher = {Sage},     author = {Marsick, Victoria and Watkins, Karen and O'Conner, Bridget N.},     editor = {Malloch, M. and Cairns, L. and Evans, K. and O'Conner, Bridget N.},     date = {2011} }  \end{filecontents}  \addbibresource{\jobname.bib}  \begin{document}  \ldots slightly adapted Biggs' (\citeyear{biggs1987, biggs1999}; see for a similar model \citeauthor{marsick2011}, \citeyear{marsick2011}) model of  \ldots  \end{document}   However, the output is only:     ... slightly adapted Biggs’ (1987, 1999; see for a similar model Marsick, Watkins, and O’Conner, 2011) model of ...   As you see BibLatex prints an "and" instead of an "&". It seems as \citeauthor is only thought to be used as in-text citation (there the "and" is correct).  I guess I could make my life a little bit easier by using the natbib option (see ). However, that changes some formations that I don't want to have changed.  My question therefore is: How do I get the ampersand (&) into the my citation without globally changing the and for in-text citations?


Besides electromagnetic and graviational waves, are there any other waves known to travel through empty space?

In the same way as there are electromagnetic and gravitational waves that update the information on their respective field, is there an analogue for the weak and strong forces?


I have this nut that is attached to my bed. However, I don't have access to the bed and hence need to guess the size of this nut so that I can buy the tools for it. Anyone know roughly how big this nut is and what size spanner I would need?   I'm planning on buying this wrench set and would like to know if one of them would fit this nut.   Thanks in advance :)

This is my first time posting in this forum but I wanted to get some help from y'all regarding removing a bolt from my bed frame. I bought a used bed frame and I need to dismantle it to shift it into my room. Here is an image of the bolt.   Could you please tell me what tools I would need to remove this screw (the silver nut on the left) as well as how I should go about doing it. Thank you, I really appreciate the help from this community :)


I want to start learning partial differential equations, but I know that for me the joy of self-study depends a lot on the book/material (I really liked James Stewart's calculus but hated some of my statistical books just by the way they handled the topics and how 'dry' they brought it).   Naturally, I am aware that this is a matter of taste and there is probably no study book that is universally liked. However, I would still love some advice and hear which book you found good on this topic. Preferably something that is more on applications and exercises than on proofs and theories. Also since I am doing it for self-study I really need something for which I can buy a solution manual or for which solutions to exercises can be found online.   Lastly, if it possible it would be nice if it also covers the basics of differential equations as a refresher.

What is a good PDE book suitable for self study?   I'm looking for a book that doesn't require much prerequisite knowledge beyond undergraduate-level analysis.  My goal is to understand basic solutions techniques as well as some basic theory.


How can I create my own team in Pokemon Go. Can I join any other team? If yes, how?  I've been playing for the last 4 days and I am not able to understand the team feature completely.

I made it to level 5 in Pokemon GO, but the game didn't ask me which team I wanted to join and I am currently not affiliated with any team.  Is there something I have to do in order to pick a team, or should I have been given a chance to pick a team upon leveling up?


How to prove that distance between two neighboring primes can be arbitrarily large? Thanks for help, John

Deduce that there is a prime gap of length $\geq n$ for all $n \in \mathbb{N}$   Show that if $2^n - 1$ is prime, then $n$ is prime.   Show that if $n$ is prime, then $2^n - 1$ is not divisible by $7$ for any $n > 3$.       I'm not really sure how to do the first bit. For the second one, I'm not sure if this is correct but I have this: If $n$ is not prime, then $n = a b, a, b > 1$. Also $2^n - 1 = (2 - 1)(1 + 2 + 2^2 + .... + 2^{n-1})$. So if we substitute for $n = ab$, we get $(2^a)^b - 1 = (2^a - 1)(1 + 2^a + (2^a)^2 + .... + (2^a)^{b - 1})$ which is now composite and so if $n = ab$, then $2^n - 1$. This means that $2^n - 1$ is prime if $n$ is prime. For the last one, we have a hint "Follow the example in lectures to show that $2^n - 1$ is not divisible by $3$", but I missed this lecture and haven't had a chance to get the note, so can someone help me with the divisible by $3$ bit and then I can try the divisible by $7$ bit myself.   Thank you  EDIT: I found a simpler proof for the second bit online:     Supposed $n$ is composite, it can be then written in the form $n = ab, a, b > 1 \implies (2^a)^b - 1$ is prime with $b>1$ and $2^a>2$, contradicting statement $1$.   What is statement $1$? Maybe then I can understand why it contradicts it.


I am reviewing the decimal expansion of real numbers in the context of real analysis.  I am learning the ternary expansion, but I don't understand the following statement:  $$x=\frac{10}{27}=0.101=.100222\dots$$  In a ternary expansion, I should be able to write: where $a_k\in\{0,1,2\},$  $$x=\sum_\limits{k=1}^\infty a_k\frac{1}{3^k}.$$  So I understand that the second inequality means:  $$x=\frac{1}{3}+\frac{0}{3^2}+\frac{1}{3^3}=\frac{10}{27}.$$  But why is the final equality true with $2^s$ keep going? What is the analogy in the decimal expansion?

I'm told by smart people that $$0.999999999\ldots=1$$ and I believe them, but is there a proof that explains why this is?


I set a background image (below) but it's not displaying while editing, and yes I'm not in ortho mode.  Any ideas?  Also attached a screenshot.  Update: this above part is now answered in comments—you must be in one of the preset ortho views or the camera view, and not the general ortho view or the perspective view.  I'm also interested in making this show up in my Cycles render, but it's not showing up despite having checked the Transparent checkbox under the Film panel.  Threads I've already read include:

How do I put a backdrop behind the model that I am creating so that I can compare the picture to the model while editing?


I am a new Linux user and I have ubuntu 20.04 running in Lenovo laptop. It was working fine all of sudden it started giving authentication error. I tried restarting the system and since then I am getting the below error. Its stuck forever and not moving anywhere. Please can somebody help me. Below is the screenshot of the error

dev/sda1: clean, 552599/6111232 files, 7119295/24414464 blocks   After I turn on my laptop this message appears. The system never boots, the message just stays there.


If $n$ is a positive number, let $\mathbb{Z}_n^*$ be the subset of class representatives in $\{1,..., n-1\}$ which are relatively prime to $n$. Show that if $[a],[b] \in \mathbb{Z}_n^* $ then $[ab] \in \mathbb{Z}_n^*$. I think $[a]$ is an equivalence class. But what does it represent? If $a = 1$, what does $[1]$ imply? Update: this is what I understand so far. For example, let n = 5, a = 2. Then relatively primes of n is {1,2,3,4}, and [a] = {2,4} because it's only 2 in {1,2,3,4} that has residual when divided by n = 5. Is this correct? Update: My thought on proving the problem. Let [a] = {a + kn | k $\in \mathbb{Z}_n^*$},  [b] = {b + ln | l $\in \mathbb{Z}_n^*$}. Pick an a' from [a] and b' from [b]. I can say a' = a + kn, b' = b +ln. Then a'*b' = ab + n(ak + bk + $nk^2$). This is congruent to ab mod n. Therefore [ab] $\in \mathbb{Z}_n^*$. Would this be an appropriate proof?

Let $a,b,n$ be integers such that  $\gcd(a,n)=\gcd(b,n)=1$. How to show that $\gcd(ab,n)=1$?   In other words, how to show that if two integers $a$ and $b$ each have no non-trivial common divisor with and integer $n$, then their product does no have a non-trivial common divisor with $n$ either.     This is a problem that is an exercise in my course.   Intuitively it seems plausible and it is easy to check in specific cases but how to  give an actual proof is not obvious.


I need to get count of different values of meta_key:  Let's say I've got meta_key $class & there's only three different values: 1, 2 & 3.  //My WP_Query  $ads = new WP_Query(array(     'post_type' => 'ads',      'meta_key' => 'ads_class',      'orderby' => 'meta_value_num' ));       if ( $ads->have_posts() ) :      //Do stuff   //Now I need to know how many have ads_class of "1", "2" and "3" - all as different vars

I know how to get a custom field value for a specific post.   get_post_meta($post_id, $key, $single);   What I need is to get all the values associated with a specific custom post key, across all posts.  Anyone knows of an efficient way to do this? I wouldn't want to loop through all post id's in the DB.  Example:  4 posts all with different values for a custom field called 'Mood'. 2 posts have the value 'happy', 1 post have 'angry' and 1 post has 'sad'  I want to output : across all posts we have: two happy, one angry and one sad author(s).  But for LOTS of posts.  What I'm looking for is either:   a WP function to get this. or a custom query to get this as efficiently as possible.


I have just finished single variable differential/integral calculus (with a little bit of infinite series).  I'd like to jump right into the multivariable stuff; given that I intend to major in engineering (definitely not pure mathematics). Which textbook would you recommend that covers integral/differential calculus of several variables?  I am more interested in the computational stuff than the "proofs" if that makes sense.  Some I've heard of are  Stewart / Spivak - Calculus on manifolds/ Anton/ Howard/ Edwards  Thank you very much!

I am looking for a multivariable calculus book that is really physics oriented.  Anyone know of any?  EDIT: My wife is looking to brush up on multivariable at the same time she needs to brush up on the related physics.


As I understand it, both the X-Men and the Inhumans receive their powers due to their innate genetics (as opposed to supers that got it from an external source, like Spider-Man who got it from a radioactive spider).  In the mainstream, Earth-616 comics universe, what is the difference between these two groups? Do they have different sets of genes that both happen to express themselves as superpowers? Or is there some other important difference?

What's the difference between those two? Aren't Inhumans supposed to be an evolution of the human race "forced" by the Kree? Which is almost the same as Mutants, the natural evolution of the human race...  What exactly am I missing?


I was working on TexStudio and accidentally pulled out the plug, the PC turned off immediately (no battery). It happens regularly. However, this time when I restarted it and tried to open the .tex file it was completely blank, the same thing happens with the respective pdf file too. I have tried to open it with several other apps (word, notepad, Notepad++, Texmaker, Overleaf, etc.) and nothing works. In particular, when I open it with Notepad++ the text reads NULL NULL NULL...., just like someone put blanks on my code and ran it.  The size of the code is still several hundred Kbs and the system had a Windows 10 update earlier that day.   Do you have any idea on what can possibly have happened?  Is it possible to retrieve the code?

I wrote all my coding in the .tex file. The next day when I opened it the coding is all gone and the pdf file is opening with it and is displayed as an output. How do I bring back my coding?


For $(x, y) \in \mathbb{R}^2$ to be a constructible point, we must necessarily have $[\mathbb{Q}(x, y):\mathbb{Q}] = 2^r.$ According to a book I'm reading on Galois theory, questions about sufficiency are much more difficult.  There is a nice exercise in the book to show that $\mathbb{Q} = F_0 \subseteq F_1 \subseteq \cdots \subseteq F_r = \mathbb{Q}(x, y)$ with $[F_{j + 1} : F_j] = 2$ is a sufficient condition for $(x, y) \in \mathbb{R}^2$ to be a constructible point. But is just $[\mathbb{Q}(x, y):\mathbb{Q}] = 2^r$ a sufficient condition for $(x, y) \in \mathbb{R}^2$ to be a constructible point?

Let $F\subseteq\mathbb{C}$ be a Galois extension of $\mathbb{Q}$ such that $[F:\mathbb{Q}]=2^n$; then all elements in $F$ are constructible.    Added.  Here is what I have so far.  Since there exist the finite normal extension $F\subseteq\mathbb{C}$ over $\mathbb{Q}$ which contains an element say, s, then s has a degree of power of 2. From group theory we have 2 propositons we could use. 'A group $G$ is solvable iff it has a normal series whose factors are abelian', and also 'If $G$ is solvable and $N\triangleleft G$, then $G/N$ is solvable'. Then we can say that the galois group F has a normal series $\{e\}=G_0\triangleleft G_1\triangleleft\cdots\triangleleft G_n=\mathrm{Gal}(F/\mathbb{Q})$, whose factors have order 2. Thus there must exist intermediate fields $\mathbb{Q}=F_0 \subseteq F_1 \subseteq F_2 \subseteq\cdots\subseteq F_n=F$, such that $[F_{j+1}:F_j]=2$ for all $j$. Now this is where I got stuck. Next I need to somehow show that $F_{j+1}=F_j(s_j)$, where $s^2_j$ is an element in $F_j$. Then I think I can conclude that if $s_j$ is constructible than every element in $F_{j+1}$ is constructible... then with $F_n$ is constructible...


So I've got one server box that has two network cards. One connects to the Internet via ISP router (and serves a website) and one connects to a LAN. The thing is that in order for everything to work right, I need after each reboot to run these commands:  sudo route del default gw 192.168.10.1   #the gateway of the LAN card sudo route add default gw 10.10.10.1     #the gateway of the ISP router card   My question is, how can I make these commands run automatically at system reboot (and not at any user logon, as nobody logs into the box)?

After upgrading to 11.10, my system is "forgetting" the default route to the internet every time the machine gets rebooted.  It "remembers" the route to the office (on a second NIC).  In my /etc/network/interfaces file I have both NICs configured as static and specify the IP, netmask AND gateway for each.  But the gateway for the external NIC is no longer being set at boot time (though it worked perfectly in 11.04).   I'm wondering if it might be related to the "waiting for network configuration" problem that I and others seen.  Either way, I need a solution or at least a work-around.  As requested... route -v (after I manually added the eth1 default gateway, of course -- to see it before, imagine the eth1 gateway line missing):  Kernel IP routing table Destination     Gateway         Genmask         Flags Metric Ref    Use Iface default         216.199.48.57.n 0.0.0.0         UG    0      0        0 eth1 default         192.168.42.1    0.0.0.0         UG    100    0        0 eth0 192.168.42.0    *               255.255.255.0   U     0      0        0 eth0 216.199.48.56   *               255.255.255.248 U     0      0        0 eth1   /etc/network/interfaces:  # The loopback network interface auto lo iface lo inet loopback  # Office network auto eth0 iface eth0 inet static         address 192.168.42.4         netmask 255.255.255.0         gateway 192.168.42.1  # Internet auto eth1 iface eth1 inet static         address 216.199.48.58         netmask 255.255.255.248         gateway 216.199.48.57


Can I breed volt absorb from one female pokemon in the same egg group as Pachirisu directly to a male Pachirisu lacking the ability? And if so, where can I find pokemon with the hidden ability in pokemon oras/xy?

I want to legitimately breed a competitive team, but I don't know how to breed for hidden abilities unless I just breed two Pokemon who have their normal ability(s) together until I breed one with a hidden ability. Does someone know a useful trick or item I could use?


I want to pass a csv of int  1,2,3,4,5,6,7   to a stored procedure so that I can use the passed-in values in an IN() so that   IN(1,2,3,4,5,6,7)   Is that even possible?

Possible Duplicate:          I have seen  in SQL. I wonder how would you approach the opposite problem: splitting coma delimited string into rows of data:  Lets say I have tables:  userTypedTags(userID,commaSeparatedTags) 'one entry per user tags(tagID,name)   And want to insert data into table  userTag(userID,tagID) 'multiple entries per user   Inspired by  question  EDIT  Thanks for the answers, actually more then one deserves to be accepted but I can only pick one, and the  with recursions seems pretty clean to me. It works on SQL Server 2005 and above.   For earlier version of SQL Server the solution  can be used.  For working with text data type  will be helpful. Thanks again.


Under power management is a feature for "Selective Suspend" in which Windows will suspend devices as it sees fit to save power. Is there a way to manually set a device to be suspended, rather than wait on selective suspend? I'm trying to test the design of a USB device to handle waking up appropriately after it's been suspended.

I have 2 non-system SATA HDDs which are not mapped to a dir and normally kept 'offline' on my Windows 7 OS. Even this way they spin up from time to time, including but not limited to windows update times.  It's easy on Linux but, what is the best way to spin down a HDD on demand using as small 3rd party software as possible on Windows? Or even, is there a 3rd party software allowing this?


How potentiate $(x^a)^b$ for complex numbers?

Regarding ,  it is not possible to combine complex powers in the usual way:  $$ (x^y)^z = x^{yz} $$  There was mention of multi-valued functions, is there some theory that makes this all work out correctly?


I have a website where users register using a username but my RewriteRule only works on one-name usernames and two-name usernames that are separated by an underscore or hyphen but if you use an @ sign before your username or you use a space,it doesn't work e.g if one registers using 'Tom', 'TomClark', 'Tom-Clark' or 'Tom_Clark' they can be able to go to their profile page but if they register using 'Tom Clark' or '@Tom Clark',they get Error 404 object not found.I want my RewriteRule to recognise spaces and @ sign.  Here is my .htaccess page:  RewriteEngine On RewriteRule ^([a-zA-Z0-9_-]+)$ profile.php?u=$1 RewriteRule ^([a-zA-Z0-9_-]+)/$ profile.php?u=$1

I need to set up some RewriteRules to redirect a URL which has a space in it. I've tried this:  RewriteRule ^article/with%20spaces.html$ /article/without_spaces.html [R=301,L]   ... but it doesn't work. Putting in a space instead of %20 causes a 500 Internal Server Error. How do I add a space?


The biggest problem with OS X that bothers me a lot is that when you are working with multiple applications and trying to switch between applications with mouse: first you have to click on the application and then start using it.  As an example, let's say we have two text editors that we are typing in each of them separately. Now lets say we want to copy a piece of text from first window to the second one. Based on OS X's behavioral semantics, you have to select the first window with a mouse click and then again press the mouse click to select a piece of text. This sometimes brings down my productivity by a lot in different applications.  In Microsoft Windows applications, there is no such concept. For the same scenario, if you click on some text on the a un-selected window, it will instantly start selecting the text without the need for selecting the application first. This is only one simple example.  The question is, is there anyway to enable a feature like this in OS X?

I would like to enable click-through on all windows. Is this possible on Lion?  To be more specific, "click-through" as defined by Apple in the  means "that the user can activate the item when the containing window is inactive."       An item that provides click-through is one that a user can activate with one click, even though the item is in an inactive window. (To activate an item that does not support click-through, the user must first make the containing window active and then click the item.) Although click-through can make some user tasks easier, it can also confuse users if they click items unintentionally.


I have this device is not working since I upgraded Ubuntu from 14.04 to 16.04. Should I enable it? and how?

After upgrading to 15.04, I have one additional driver (it did not appear in 14.10). What is the purpose of this driver and should I enable it?


I want to know if Luke and Leia being Vader's kids becomes public knowledge? Presumably people would be more suspicious of them if they knew the truth.Does Poe know his General is connected to the Empire?

Did it ever become "public" knowledge that Anakin was Darth Vader, after he died? There were of course several people at the Viking Jedi funeral of Darth Vader, but did the others (not including Leia) know he was Anakin and the father of Luke and Leia? EU or canon?


I am trying to boot from a usb drive.  I created the usb on an ACER running Win 7 Home premium.  I used the ubuntu-13.04-desktop-1386 using the universal USB installer.  I am trying to install on a Dell inspiron 600m.  When I try to boot, I get a message "SYSLINUX 4.06 EDD 2012-10-23 copyright (C) 1994-2012 H. Peter Anvin et al" The next line has a blinking underscore.  It will not allow me to enter anything.  What do I do? Did I try to use the wrong version Linux? If so, what should I use?    I don't care which version from 12.04 - 13.04 I load.  I couldeven use an earlier version if it will work.  I just want it to boot, so I can install linux as the only OS on this machine.

I am trying to install linux on my laptop, a Toshiba Satellite C6550-S5200. I did it once but something happened so I removed it then I had to destroy all data on hard drive so now I have nothing on it. Well I got a iso file burned to a CD and to a flash drive. With the flash drive I get.   SYSLINUX 4.06 EDD 4.06-pre7 Copyright (C) 1994-2012 H. Peter Anvin et al  With the CD it will start booting it but somewhere loading it up, the dots turn all orange and stay that way and my CD drive turns quiet.  Oh and some more info the images work because I tried loading them up on another pc and it worked just fine.  I manage to get the CD to boot I just had to let me pc boot up first then insert the CD and have it boot the CD then. Once I get done installing ubuntu it works fine but I have to leave the PC on 24/7 for if I turn it off the PC will freeze 5-10 seconds after booting back up no matter how I install it.


How to solve for:  $\int \frac{dx}{\left(x^2+4\right)^2}$  What I have tried so far:  Let $x = 2 \tan \theta$ so that $dx = 2 \sec^2\theta d\theta$    $I = \int \frac{2 \sec^2 \theta d\theta}{\left(16 \sec^4\theta \right)^2}$  Not sure where to go from here.  The answer that I expect:  $C + \frac{1}{16} tan^{^-1} \frac{x}{2}+\frac{1}{8}x(x^2+4)^{^-1}$

I am in the middle of a problem and having trouble integrating the following integral:  $$\int_{-1}^1\frac1{(1+x^2)^2}\mathrm dx$$  I tried doing partial fractions and got:  $$1=A(1+x^2)+B(1+x^2)$$  I have no clue how to solve this since it is obvious there is no way to cancel out either $A$ or $B$ to get the other variable. Please guide me.  Thank you.


I had installed Ubuntu 18.04  from a usb drive in an hp/amd Windows machine  and I erased windows. installation completed but soon discovered that my network adapter was not found by the OS. how should I troubleshoot...and would like to do this installation again..

On this site I see hundreds if not a thousand questions being asked about issues with a Wireless LAN adapter not being detected/recognized by Ubuntu. Some mainstream adapters appear to be utterly broken in Linux support, while others just require some simple steps to get it to work.  The options to get it to work appear to be infinitely huge and I have no clue where to get started!  What is considered 'best practice'? What order of things to try is most efficient in terms of time, effort and imposes minimal risk to my Ubuntu installation? Please help me save time and guide me what to do, step by step.


Example of noncommutative ring in which all nonzero elements are   invertible.   I was thinking along Matrices in $(2,\mathbb Z$), but some nonzero matrices are not invertible.  Can someone provide me with an example?

From Wolfram Alpha I have that the definition of a division ring is;  "a ring in which every nonzero element has a multiplicative inverse, but multiplication is not necessarily commutative". Can someone give me an example of a division ring  where multiplication is commutative and one where it is not commutative?


I am beginning to make friends with SubSonic 3.0.0.3 - SimpleRepository. Since you/I have to create every object class, so I made a simple code below, just to save some time.  My only question is, does my mapping are correct (DB DataType to .Net DataType)?  Here's the simple code:  public string CreateClassEntity(string ConnectionSring, string TableName)         {            SqlDatabase db = new SqlDatabase(ConnectionSring);              string sqlCommand = "SELECT TOP 1 * FROM " + TableName + "";             DbCommand dbCommand = db.GetSqlStringCommand(sqlCommand);              DataSet subsonicDataSet = db.ExecuteDataSet(dbCommand);              DataTable subsonicDataTable = subsonicDataSet.Tables[0].Clone();             string classEntity = "public class " + TableName + " \n{";             foreach(DataColumn column in subsonicDataTable.Columns)             {                 classEntity += "\n\tpublic ";                 classEntity += column.DataType.ToString().Replace("System.", string.Empty) + " ";                 classEntity += column.ColumnName + " ";                  classEntity += "{ get; set; }";             }             classEntity += "\n}";              return classEntity;         }   Sample target Table (SQL 2008):  CREATE TABLE [kiss].[Users](     [ID] [int] IDENTITY(1,1) NOT NULL,     [UserName] [nvarchar](20) NOT NULL,     [UserPassword] [varbinary](128) NULL,     [UserTypeID] [tinyint] NOT NULL,     [ByPassAccessRestrictionsFlag] [bit] NOT NULL,     [IsEnforcePasswordPolicy] [bit] NOT NULL,     [PasswordExpirationDate] [datetime] NULL,     [IsPwdChangeNextLogin] [bit] NOT NULL,     [ShowLatestNewsFlag] [bit] NOT NULL,     [SortRowNumber] [int] NOT NULL,     [CreatedDate] [datetime] NOT NULL,     [CreatedBy] [nvarchar](20) NOT NULL,     [UpdatedDate] [datetime] NOT NULL,     [UpdatedBy] [nvarchar](20) NOT NULL,     [DeletedDate] [int] NULL,     [EntityTypeID] [int] NOT NULL     )   Sample Class Output:  public class Users  {     public Int32 ID { get; set; }     public String UserName { get; set; }     public Byte[] UserPassword { get; set; }     public Byte UserTypeID { get; set; }     public Boolean ByPassAccessRestrictionsFlag { get; set; }     public Boolean IsEnforcePasswordPolicy { get; set; }     public DateTime PasswordExpirationDate { get; set; }     public Boolean IsPwdChangeNextLogin { get; set; }     public Boolean ShowLatestNewsFlag { get; set; }     public Int32 SortRowNumber { get; set; }     public DateTime CreatedDate { get; set; }     public String CreatedBy { get; set; }     public DateTime UpdatedDate { get; set; }     public String UpdatedBy { get; set; }     public Int32 DeletedDate { get; set; }     public Int32 EntityTypeID { get; set; } }

For the following SQL Server datatypes, what would be the corresponding datatype in C#?  Exact Numerics  bigint numeric bit smallint decimal smallmoney int tinyint money     Approximate Numerics  float real     Date and Time  date datetimeoffset datetime2 smalldatetime datetime time     Character Strings  char varchar text     Unicode Character Strings  nchar nvarchar ntext     Binary Strings  binary varbinary image     Other Data Types  cursor timestamp hierarchyid uniqueidentifier sql_variant xml table   (source: )


I'm writing my PhD thesis using LaTeX. The text is becoming bigger and I'd like to know the LaTeX experts' opinion. What's the best way to deal with a big document and why? A single .tex file (thesis.tex) or divide the document in smaller .tex files, like introduction.tex, materials.tex, results.tex, etc. and compile with something like:  \documentclass[<options>]{<document type>} \usepackage{<packages used>} \begin{document} \input{introduction} \input{materials} \input{results} \end{document}

Why is it recommended to split a large document into several parts and include them with \include? Is it only a relic of the past times when computers and LaTeX compilers were slower, or is it still up-to-date? What are the pros and cons of this practice, also in terms of interaction with other external tools (version control, find/replace, et cetera)?  Motivation: I've found a recent discussion that mentions this practice ( , ), as well as a comment that criticizes it in an answer to . A couple of months ago, I asked the same question in a comment to , but it's probably better to ask this here again as a "real question".


I need to convert exponential values to log and back to exponential. Using it for . What i have tried,  Example A:  a = 5.45e-320 5.45e-320  b = Math.log(a) -735.1316071514119  Math.exp(b) 5.45e-320   Example A is working fine for me but when i try this example  a = 2e-8 2e-8  b = Math.log(a) -17.72753356339242  Math.exp(b) 2.0000000000000004e-8    Expected and needed Output: 2e-8  I am curious to know how this Math.log and Math.exp works, I researched on many documents but didn't find my answer.  Please correct me if i am wrong here, Thanks.

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


I'd like to add some math symbols to that picture. How can I make it? (I'm using another software to make the pics.)

Recently I have learned how to draw simple stuff with TikZ. I really like it. Now I wonder if it is possible to draw with TikZ on a image. Instead of pasting a image in Illustrator and adding some vectors to point something in the picture I would like to do it using TikZ. Is it possible?   For example, on a picture of a computer (PNG,etc) I would like to draw some arrows and labels saying "Keyboard", "Monitor", etc.


I've read  and , but it doesn't work to well for my use case.  I'm using the geometry and fancyhdr package. I did some 'hacking' to accomplish what I have right now, which pretty much is just that the first page has a big top-margin of 2.5in so that my fancyhdr fits in there nicely.  I only want the header on the first page though, thus I set thispagestyle{fancy}. However, the margin still applies to the second page and I don't know how to change that.  newgeometry wouldn't work, because I don't know where exactly the first page will end. Of course I could do some more hacking and just do trial&error, but I thought maybe there is some better way.  In short: Is there a way to change the margin after the first page?  Here is a MWE:  \documentclass[a4paper,10pt,oneside]{article} \usepackage[english]{babel} \usepackage[letterspace=150]{microtype} \usepackage{fancyhdr} \usepackage[top=2.5in,bottom=1.5in,right=1.5in,left=1.5in,headheight=95pt,headsep=2cm]{geometry} \usepackage{lipsum}  \thispagestyle{fancy} \pagestyle{empty}  \renewcommand{\headrulewidth}{0pt}  \fancyhead[C]{     \fontsize{22}{22}\scshape{I am\\ a\\ title}\\     \fontsize{12}{25}\scshape{Sub {\large\textperiodcentered} Title} }  \begin{document} \lipsum[1-2] \lipsum[1-4] \lipsum[1-2] \end{document}

I have a document class that auto generates header from some user input. The problem is the first page should have a different page header than the others and the headline can be multi line. So \headheight is too small. Here is a demonstration of the problem:  \documentclass[twoside]{scrartcl} \newcommand{\longfirstpagehead}{% \begin{minipage}{10cm} some\\long\\text\\text\\text\\text\\text\\text \end{minipage}} \newcommand{\normalhead}{normal} \usepackage{scrpage2}  \newpagestyle{firstpage}{%     {\longfirstpagehead\hfill} %twoside links     {\longfirstpagehead\hfill} %twoside rechts     {\longfirstpagehead\hfill} %oneside     (\textwidth,1pt) }{%     {\pagemark\hfill} %twoside links     {\hfill\pagemark} %twoside rechts     {\hfill\pagemark} %oneside } %  \newpagestyle{normal}{%     {\normalhead\hfill} %twoside links     {\normalhead\hfill} %twoside rechts     {\normalhead\hfill} %oneside     (\textwidth,1pt) }{%     {\pagemark\hfill} %twoside links     {\hfill\pagemark} %twoside rechts     {\hfill\pagemark} %oneside } %    \pagestyle{normal} \AtBeginDocument{     \thispagestyle{firstpage}}  \usepackage{blindtext} \begin{document}     %\vspace*{1cm}     \blindtext      \blindtext     \pagebreak \end{document}   I tried to read the height with \settototalheight and:   add a \vspace at beginning of document (unnice hack):  still the bad box warning (of cause) first section has different alignment  manually change \headheight in pagestyle  text height and page foot is wrong (can't change this because some scoping?)  use Komascript in pagestyle  \recalctypearea warning  geometry in pagestyle  pretty much the same problem like the manual attemp    So I would like to change the \headheight for the pagestyle firstpage, but the page should still have the same page margins, etc. The problem is that this has to work with \thispagestyle. (Better Ideas are also welcome) Something like \thispagegeometry in geometry would be great. ;)


Show that $a^2 + b^2 + c^2 \geq ab + bc + ca$ for all positive integers $a$, $b$, and $c$.  I am not sure how to approach this problem. Should I divide this problem into multiple cases based on whether $a$,$b$,$c$ and odd/even or is there a more general solution?

How can the following inequation be proven?  $$a^2 + b^2 + c^2 \ge ab + bc + ca$$


I had my raspberry pi 4 (lost due to mistake), and I have to restore its data from my windows computer. It is an SD card, has two partitions:  system-boot USB Drive.  I also know how much windows and Ubuntu's drive formatting is different. So, how do I do it? Is there a tool or any kind of program for supporting two formatting's at the same time? Additional information  I am on windows 10 64bit I used 20.04LTS in past

I have two questions on ext4:   Is there currently a way to mount an ext4 partition in Windows (XP/Vista/7) to get basic read support? If not, are there any plans to support this someday?


I am trying to do something that I imagine is quite straightforward but I am new to C/C++ so it is proving a little bit tricky. Essentially I am trying to remove a single whitespace from data contained within a .txt. Each piece of data is on a separate line:  01011 0 11100 1 00001 0   and so on. I have been able to count the number of lines, and the size of each string (including the whitespace) however I want to lose the whitespace located within the data. My code for reading the data in (including whitespace is as follows):  std::ifstream myfile ("random.txt"); std::string str;  if(myfile.is_open())                 {                 while (std::getline(myfile, str))                     {                     i++;                     Size = str.size();                     data_input[i] = str;                     line_num = i;                     array_count = line_num * Size;                     }                  i = 0;                 }   I have looked at various other posts but can't seem to find one that fits what I am trying to achieve. Any help would be appreciated.

What is the preferred way to remove spaces from a string in C++? I could loop through all the characters and build a new string, but is there a better way?


My goal is to download all attachments of a given Case. I was managed to perform the needed queries to and I have a pointer to the ContentVersion object I need. They problem is that I don't know how to download the attachment. I believe I need the VersionData field, which holds the file in binary format. Another limitation that I have is that I'm using a Linux environment by means of its CLI prompt. I already made an authentication to SF by using SFDX API provided by SalesForce, but I cannot find a way to combine SFDX API with REST API's GET command to fetch the needed file so it will be downloaded to my Linux machine. Please advise. Uri

I am trying to do an export of approx 30,000 attachments in our Salesforce Org,  Would anyone have been through a similar exercise and can advise best practice or the best way / tool to do this?  Kind Regards  matt


I'm trying to calculate a polygon area. This is the polygon and the attribute table:    When i open field calculator and use the Geometry--> area$, the area result for ID 1 is (in squere meters) 1809477.67:    but when i use the Export/Add geometry column tool, two things happen:   a new layer been created named "added geom info"- why the data isn't created in the polygon attribute table? the area result is (in squere meters): 1799292.92 - why i get different results?        When i measure the area in ArcGIS 10.3 - the result was 1799292.92 squere meters.  I also red      and didn't found any suitable answer.

Using QGIS, if I load a polygon layer and make a new column, how do I fill that column with the:   area of each polygon and another column with length of the perimeter of each polygon?


I have a class for an object, and if a user attempts to supply a negative number to it's constructor I want to output a warning telling them that they have provided an invalid number in the form of  System.out.println("ERROR ON LINE " + Thread.currentThread().getStackTrace()[2].getLineNumber() + ": You have provided an invalid number.\nSetting to default.");   EDIT: I set the values to a default values in the system, I don't want the program to terminate.  What I really want to know is how I do automagically find the [2].

How to print line numbers to the log. Say when outputting some information to the log, I also want to print the line number where that output is in the source code. As we can see in the stack trace, it displays the line number where the exception has occurred. Stack trace is available on the exception object.  Other alternative could be like manually including the line number when printing to the log. Is there any other way?


We can easily find in many online sources, including here in Cross Validated, the claim that outliers shouldn't be removed from data (at least without a good reason). In the thread below, for example, this is the general advice given by most users:    I'd like to quote this claim from a trustworthy source, but I couldn't find such statement in any introductory statistics books.  Is this belief just general wisdom of the crowd or there is something to support it?  EDIT (Justification that this question is not duplicated)  Please, remark that this question is asking for academic references (e.g. the name of a book or a paper) for the claim (posts from CV are no enough for my current needs). Something that could be quoted in a business report or in an academic paper. The question is not concerned with the problem of removing outliers being a good practice or not, as previous questions here in CV.  Possible Answer  The user davefournier suggested in the comments the book:  Robust Statistics, 2nd Edition Peter J. Huber, Elvezio M. Ronchetti ISBN: 978-0-470-12990-6  I just glimpsed at it and it seems promising. I still need to read it a little more to be sure if directly answers the question.

I looked for a way to remove outliers from a dataset and I found .  In some of the comments and answers to this question, however, people mentioned that it is bad practice to remove outliers from the data.   In my dataset I have several outliers that very likely are just due to measurement errors. Even if some of them are not, I have no way of checking it case by case, because there are too many data points. Is it statistically valid than just to remove the outliers? Or, if not, what could be another solution?   If I just leave those points there, they influence e.g. the mean in a way that does not reflect reality (because most of them are errors anyway).   EDIT: I am working with skin conductance data. Most of the extreme values are due to artifacts like somebody pulling on the wires.   EDIT2: My main interest in analyzing the data is to determine if there is a difference between two groups


Let $G$ be a group and $H$ a subgroup of $G$. Suppose $g^2\in H$ for all $g\in G$. Show $H$ is a normal subgroup of $G$. I tried lots of methods, but failed. Any suggestion? Thanks.

Let $H$ be a subgroup of a group $G$ such that $x^2 \in H$, $\forall x\in G$. Prove that $H$ is a normal subgroup of $G$.    I have tried to using the definition but failed. Can someone help me please.


I need to know the flight number for the flight to Orlando, Florida, from Gatwick in London, UK in August 2011, via Virgin Airlines, that I missed, but I don't know how to find it. Where can I find the flight number?

The question  only deals with flights in the US sourced from the  . Is there some similar source for EU, Asia etc?


Let $n = p_1^{a_1}p_2^{a_2} \dots p_k^{a_k}$. Show that $d(n) = (a_1+1)(a_2+1)\dots(a_k+1).$  How should I go about this? I tried to first show that the divisor function is multiplicative and use that result to prove the statement, but it seems that the multiplicativity depends on the result I'm actually trying to show? Any hints would be appreciated.

Let $n$ be a positive natural number whose prime factorization is $n=p_1^{a_1}p_2^{a_2}\cdots p_k^{a_k}$, where $p_i$ are natural distinct prime numbers, and $a_i$ are positive natural numbers.   Using induction to show that the number of divisors of $n$ is $$(a_1+1)(a_2+1)\cdots(a_k+1)$$


Been looking around and can't see to find any information on how to enable alt+right click for window resize?  edit  My mistake  Running Unity 12.04, I am logged in under failsafe graphics mode as i can't get my 590GX Nvidida card to boot up without being in safe, but thats another problem.  Currently, my alt+click works and i can drag windows around.   But i can't currently, alt+right-click to resize.

The title says it all. I want to resize windows with an right click while holding the alt key, instead of the new default alt+middle click.  I have found no way to enable this behaviour in 13.04. The gconf-Key suggested in this , doesn't seem to exist any longer.


I find that good morning is used both at the beginning of conversations (as in, "Good morning! How are you today?") and as a means of saying farewell.  The same is true for good evening. In contrast, you never hear people greeting each other with good night then launching into conversation.  It's always used as a greeting on its own ( as when passing someone by in the street) or as a farewell remark.  I don't know if this is regional or not (I'm from Pennsylvania), but it seems quite arbitrary.  Any thoughts?

To start off let us construct a situation were I am walking along and I pass another person. Depending on the time of day and to be polite I say one of the following:   "Good Morning!" "Good Evening!" "Good Night!" "Good Day!"   Now 1 and 2 are common welcoming and polite gestures and I have no problem with their use. However the problem lies with 3: Why is it so dismissive compared with 1 and 2?  If I said "Good Night!" to somebody when walking at around 11 p.m why does it sound like I am putting them to bed?  Finally as a related matter, why is 4 not used too often? In other languages 4 seems to be more common then an equivalent "Hello!" and sometimes 4 and "Hello!" posses the same.meaning.


So, I saw a similar question explaining that Moonbeam and other similar hazard spells don't deal damage when they attack. However, since moonbeam is able to be moved, are the enemies considered 'entering' the spells AOE when it moves on to the tile they are standing on (if it comes to rest there)? The other answers and the wording lead me to believe that it could go either way, so I am curious to get some of your opinions.

The description of the moonbeam spell (PHB pg. 261) says:  When a creature enters the spell's area for the first time on a turn or starts its turn there, it is engulfed in ghostly flames that cause searing pain... On each of your turns after you cast this spell, you can use an action to move the beam 60 feet in any direction.  We read this to mean a creature takes damage from moonbeam when any of the following conditions are met:  It begins its turn inside the moonbeam It enters the moonbeam on its turn The creature finds itself inside the beam on another character's turn, no matter how it got there  The creature will not take damage in the following instances:  A creature moves from one part of the beam to another (obviously it had to take damage, but it won't take more damage) A creature is in the beam after having been inside the beam already on that turn.  Following these assumptions, our druid cast a moonbeam and did damage to two enemies, Bob and Frank. On their turn, they took damage again, killing Bob. Frank left the beam. On the druid's next turn, she moved the beam in a circular motion, not exceeding 60 total feet of movement, and in the process the beam came in contact with a dozen enemies and ended on Frank. All dozen enemies received damage, as they were inside the beam at some point during the turn. On Frank's next turn, he again took damage for the fourth time and died. On each of the druid's turns, she moved the moonbeam around like this until the fight ended (it did not exceed the time limit and she made all concentration checks). Is this a legitimate use of moonbeam? It seems awfully powerful for a level 2 spell.


Is there a way in JavaScript to get element's visible part? E.g. I have elements that are being scrolled and I need to know whether the element is fully visible or partially and understand what part is visible.

Is there an efficient way to tell if a DOM element (in an HTML document) is currently visible (appears in the viewport)?  (The question refers to Firefox.)


I'm trying to set up a simple macro to generate a column of values incremented by a specific value up to a specific value. For the current example, I want to produce a column ranging from 0 to 97.9 and incremented by 0.1. Here is the code I use:  Set Inp = Workbooks("Effective Weight.xlsm").Worksheets("Input") Set Res = Workbooks("Effective Weight.xlsm").Worksheets("Results")  i = 1 Res.Cells(i, 1) = 0  Do While Res.Cells(i, 1) <= 97.9     Res.Cells(i + 1, 1) = Res.Cells(i, 1) + 0.1     i = i + 1 Loop  MsgBox (Res.Cells(i, 1))   This results in a final value of 97.9999999999987. I was expecting to be 97.9. because of the higher number of decimal points, the loop also runs one extra loop and calculates a final value of "almost" 98 instead of 97.9.  Any help on how to solve this will be appreciated

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


I have Fedora 20 installed in my laptop. I want to move on from Fedora 20 to Ubuntu 18.04.  Is it necessary to boot to windows first or can I directly boot Ubuntu 18.04 on my Fedora 20 by USB boot?

I have Fedora installed on my desktop and I want to make a live USB stick with Ubuntu to install it on a laptop. What's the easiest way to do it?


I am attempting to search for records that contain some text and limit the search results to a group of Ids. For simplicity, I'll remove the "search for text" part in this question.    The problematic query looks like this   FIND {* OR *} IN ALL FIELDS RETURNING  Lead(Id, Name, Company Where Id IN ('someId')) , Contact(Id, Name, AccountId, Phone, MobilePhone, Email, MailingAddress Where Id IN('someId'))     In the sandbox, this query returns 0 rows no matter what if I enter a Lead's Id.. However if I split the SOSL into two parts with one for Lead and one for Contact, both can return records.    Combined :   Combined with contact ID :   Lead by itself :   In the dev org however, the query works without a hitch even if I enter a Lead's ID.   Combined :   Lead by itself:   Is there some sort of setting that I should be looking for or is this correct behavior?  I know that IDs are unique to each org, the IDs shown in the examples above were taken from the org that I was testing on, I am not using the same ID everywhere to test.

To all the expert SOSL gurus lurking out there, I thought this will be an interesting one:  I have some SObjects of different types and I want to return their Name values in a single query.  In advance, I know the IDs and the ObjectTypes of the records whose Names I wish to retrieve. It seems 'wrong' to make several SOQL queries even though there aren't too many types.  So being a good platform citizen, I'm using   to retrieve what I need in a single query:  List<List<SObject>> sobjectsLists = Search.query(     'FIND {*?*} RETURNING ' +     'CustomOne__c (Name WHERE Id IN (\'a01000000000000AAA\')),' +     'CustomTwo__c (Name WHERE Id IN (\'a02000000000000AAB\')),' +     'CustomThr__c (Name WHERE Id IN (\'a03000000000000AAC\'))' ); System.debug(sobjectsLists);   But there is one problem: I must specify at least one FIND character and {*?*} doesn't cut it.     System.SearchException search term must be longer than one character: ?   I've tried this to no avail: {*a* OR *b* OR *c* OR *d* OR *e* OR ...} but even if that did work, it wouldn't help in the case that some twisted cowboy puts underscore (_) or god forbid umlaut (ä).  Any guidance on how I can get the Name of all these records at once?


Statistics textbooks go out of their way to say that 95% Confidence Intervals (CIs) do not mean that you can be 95% sure that the population parameter of interest is somewhere between the high and low end of the interval. Rather, if your sample was drawn an infinite number of times, 95% of the intervals would contain the population parameter (while 5% would not).   I fail to see the distinction. If I draw one of the infinite number of samples for which 95% CIs are calculated, aren’t I 95% certain that I’ve drawn one the ones whose CI contains the population parameter? Thus, I’m 95% certain that my CI contains the population parameter.  If someone can explain why my thinking is incorrect, I’d really appreciate it. Thank you.    Just to cause more confusion, I went to my old Statistical Methods textbook by Snedecor and Cochran (8th edition), and found the following section on Confidence Intervals:      Notice that they provide a mathematical proof for the inequality relating a population parameter value to a sample confidence interval. In addition, in their example in the middle of page 56, they explicitly state that the population parameter lies within the 95% confidence interval given, except in a 1 in 20 chance.  Snedecor and Cochran's book educated several generations of statisticians, at least here in the US. And, the mathematical proof seems pretty convincing. So now what? Do we believe what the current textbooks are saying (which do not help us in making a statement about the population parameter)? Or, do we go with Snedecor and Cochran and state that we are 95% certain the the population parameter is within our 95% CIs?   Anyone who wishes to comment, please do...I'm at a loss.

I know roughly and informally what a confidence interval is.  However, I can't seem to wrap my head around one rather important detail:  According to Wikipedia:     A confidence interval does not predict that the true value of the parameter has a particular probability of being in the confidence interval given the data actually obtained.     I've also seen similar points made in several places on this site.  A more correct definition, also from Wikipedia, is:     if confidence intervals are constructed across many separate data analyses of repeated (and possibly different) experiments, the proportion of such intervals that contain the true value of the parameter will approximately match the confidence level   Again, I've seen similar points made in several places on this site.  I don't get it.  If, under repeated experiments, the fraction of computed confidence intervals that contain the true parameter $\theta$ is $(1 - \alpha)$, then how can the probability that $\theta$ is in the confidence interval computed for the actual experiment be anything other than $(1 - \alpha)$?  I'm looking for the following in an answer:   Clarification of the distinction between the incorrect and correct definitions above. A formal, precise definition of a confidence interval that clearly shows why the first definition is wrong. A concrete example of a case where the first definition is spectacularly wrong, even if the underlying model is correct.


Can anyone give me an example of one? I know it's equivalent to finding a noetherian that isn't PID, but I'm not sure!

As stated in the question, I am looking for a Noetherian ring over which the Euclidean algorithm is not valid.  I am trying to construct non-trivial examples of Noetherian rings.  Thank you.


In the html I'm having a div tag. Between this div tag there are many other tags like span select and p tags shown like below:
   Span text   Span text   Span text   <select id="select1">     <option>1</option>   </select>   <select id="select2">     <option>1</option>   </select>
   Now how we find that how many select tags are in the div id having id="show" using jQuery.Can anyone help me to find out this.

I have the following HTML node structure:

   How do I count the number of immediate children of foo, that are of type div? In the example above, the result should be two (bar and baz).


Which preposition I have to use when talking about "airplane" or "aircraft"?   Should I use "in" like "in the car" or "on" like "on the bus?      "On the airplane / aircraft"   or      "In the airplane / aircraft"?

Examples:   In a car, van, etc. On a bus, boat, motorcycle, etc.   How can one decide which preposition to use? Is memorization the only way or is there a better way?  Note: People generally explain this by either distinguishing between open and closed vehicles or between large and small vehicles. However, the examples I've given defeat both explanations.


It would be great to add some "tools" to code blocks. For example:   Select all Copy to clipboard Expand Collapse         I also think sometimes a code block is just too big and it would be nice to display it "collapsed" in a div with just 150px height. For example, you post a SSCCE so that people can copy and paste it. There is no need to display a 600px height div because you just want people to copy the code, not to read it. But, thanks to the mentioned tools, people can still expand the block if they want.

I might just be lazy, but do you ever find it tiresome to select all the source code from a large post on Stack Overflow to copy it?  I would like a feature, possibly a Firefox extension, but preferably a JavaScript script, for automatically copying source examples to the clipboard. It's no big deal for a small snippet, but a 1000+ line posting is cumbersome to copy.  Do you guys have a better way of copying large source posts? I'm using Firefox 3.5.5 on Windows 7.


I tried to read and show a sprite, but all what I got is this error:  Exception in thread "Thread-2" java.lang.NullPointerException     at Game.MainCharacter.render(MainCharacter.java:44)     at Game.Game.render(Game.java:105)     at Game.Game.run(Game.java:149)     at java.lang.Thread.run(Unknown Source)   The sprite was opened correctly (I checked it), but I don't know where I forgot something...  Here are the classes that were used (I wrote just the code that were used): GlobalTextures Class - contains all my spritesheeets  package Game;  import java.awt.image.BufferedImage;  public class GlobalTextures {     public BufferedImage player;      private SpriteSheet character;      public GlobalTextures(Game game) {         character = new SpriteSheet(game.getCharacterSpriteSheet());         getTextures();     }      private void getTextures() {         player = character.getSprite(1, 1, 333, 472);         if(player == null) System.out.println("It doesn't exist");     } }   Player Class - there I open the character and I'm 90% sure that there's the error, but I don't know why...  package Game;  import java.awt.Graphics; import java.awt.image.BufferedImage;  public class MainCharacter extends GameObject implements Entity{       public MainCharacter(double x, double y, GlobalTextures tex) {         super(x, y, tex);     }      public void render(Graphics g) {          Game game = new Game();         g.drawImage(tex.player, (int)x, (int) y, null);      }  }   Sprite class - here I get the sprite and return the character  package Game;  import java.awt.image.BufferedImage;  public class SpriteSheet {      private BufferedImage image;      public SpriteSheet(BufferedImage image)     {         this.image = image;     }      public BufferedImage getSprite(int col, int row, int width, int height)     {         BufferedImage img = image.getSubimage((col * 2000) - 2000, (row * 2829) - 2829, width, height);         return img;     }  }   ////////////////////////////////////////////////////////////////////////////////  package Game;  public class GameObject {     protected double x;     protected double y;     protected GlobalTextures tex;      public GameObject(double x, double y, GlobalTextures tex){         this.x = x;         this.y = y;         this.tex = tex;     }  }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


EDIT: I asked the question poorly, so what follows is an edit of the original. When submitting an abstract for a presentation on research that is based on joint-work, should all authors be listed or only the presenter(s)?

I wrote a paper with  3 other students regarding my final year project in mechanical engineering. It was recently selected for a conference in NIT Delhi. Minimum one author is required to present and the price is pretty steep for the participation certificate.Should all of us attend the conference or just one of us? Does the certificate hold any value?


I have a JavaFx App, packaged and installed on my desktop, but I have a problem when I open two instances, the second one gives me a database blocking error. My idea is to launch the application only once, and if the user tries to open another copy of the app that is already open to show the original instance and not open another (prevent it from running twice if it is already open).

Sometime I see many application such as msn, windows media player etc that are single instance applications (when user executes while application is running a new application instance will not created).  In C#, I use Mutex class for this but I don't know how to do this in Java.


What's the difference between these two setences?     We did have a meeting, but it was a bit rushed.      We had a meeting, but it was a bit rushed.

Is it grammatically correct to use "did" like this?     On June 18th, I did experience my first earthquake in Japan.   I'm an ALT in Japan and on our exam for our students they had to write the statement above but without “did" but the teachers are wondering if it’s ok because they think it puts emphasis on experience. But, I dont think it is right and I cannot explain why. Any help would be appreciated.


Which is correct:        It's not raining today, isn't it?   It's not raining today, is it?

I want to ask about two sentences, and what would be the correct way to form a question:     It's very important that we eat healthy food, ...........?     Which would be the correct question tag: (isn't it) or (don't we)?      It's a must that all applicants follow the rules of the competition, ..........?    Which would the correct question tag: (isn't it) or (don't they) or (mustn't they)?   Please could you tell me the correct answers, and, more importantly, why those are correct?


Consider the three dimensional Lie algebra with basis $x,y,z$ and commutator relations $$[x,y]=y-z$$ $$[y,z]=0$$ $$[z,x]=y-z$$ I want to find a faithful matrix representation of this Lie algebra, by Ado's theorem one exists. The adjoint representation is not faithful so it needs to be some other set of matrices which give this.     I have tried to find a three $3\times3$ matrices which satisfy the above by brute force but the complexity and runtime of such a programme is extremely high. If anyone knows a solution or a practical way of finding one that would be great.

I have been trying to solve a problem concerning the Heisenberg Lie group $H$. Show that there does not exist a faithful representation $\rho:H\to\text{GL}(2,\mathbb{R})$.  Any ideas about how to solve it would be very appreciated.


My case has many issues. I am in a long-distance relationship with a man from South America. For 3 years he has been trying to enter the USA on his own and got denied 3 times a visa.  The first refusal was when he applied for his tourist visa. He waited a year and then applied to study English here in the US, they denied him again. He has done everything to prove he can return back to his country. The most recent refusal was section 214b. He wanted to do it on his own, so he applied for a student visa so he could study here in the USA and we can grow our relationship.  That’s impossible now because he’s been rejected 3 times. The first time, he applied to come for a vacation here in the USA. He put me as a family because in reality he's a distant cousin. They denied him the visa because he has family here. The next time, he applied for a student visa. The school itself in New York told him to tell immigration that he had no family here, but it was already on the record that he did say because of me.  The school offered him a chance to get a visa in the UK, so he left for a couple of months to the UK. When he came back to his home country, he decided to apply a year later again for a student visa. He was denied again even after proving ties. He has a family business and his uncle was going to pay for the whole trip.  He has no hope now and he believes that if we get married that visa will just be rejected too. He doesn’t want to do it based on marriage for fear of his past history. He wanted to try alone. Is there any way someone can offer me some advice?

Over the course of time here on TSE, I have observed individuals whose pattern of visa applications is best described as ''...     serial refusals - Two or more consecutive visa refusals issued by the same regime to the same person. Commonly for the same, or nearly the same, reasons. In some visa regimes Serial refusals can have a cumulative effect wherein the applicant's credibility is increasingly eroded, especially when the application pattern suggests a secondary agenda.   A common thread appears to be the need to visit the destination country (especially Schengen, the USA, or the UK) with a special sense of urgency. Also common in these cases are the following types of questions...   Should I just reapply once again? What are my chances? What can I do to improve my odds in the future? Can I somehow address the previous refusals to avoid them being a burden on all future applications? How can I break the pattern?      NB: This question is intended as a canonical about serial refusals. I have never been personally denied a visa.


Let $f$ such that $f(a+(m))=a+(n)$ I do not know how to prove that is well defined and that $n|m$  ,Could anyone help me, please?

I'm trying to find the ring homomorphisms from $\mathbb{Z}_n$ to $\mathbb{Z}_m$.    What I think is the answer is two cases:   1) If $m \gt n $ there is no ring homomorphism.  2) Otherwise, the homomorphism sends each element $x$  in $\mathbb{Z}_n$ to $(x \bmod m)$ in $\mathbb{Z}_m$.  Is this correct?  EDIT: Part of the ring homomorphism definition is that 1 is sent to 1


Hi i have to make a text that have different colour for each letter. I have tried to do this, it works. I want to know if there is a faster way to do this, using only CSS.  p {font-size: 36px;    font-family: sans-serif;    } .blue{color: blue;} .rosso{color:red;} .grigio{color:grey;} .oro{color:gold;} .fucsia{color:fuchsia;} .verde{color:green;} .giallo{color: yellow;} .rosa{color:pink;}   I use it in html:
Filo

I need a way to allow each letter of a word to rotate through 3 different colors. I know of some not so clean ways I can do this with asp.NET, but I'm wondering if there might be a cleaner CSS/JavaScript solution that is more search engine friendly.  The designer is including  for each page. I'd rather not have to manually generate an image for every page as that makes it hard for the non-technical site editors to add pages and change page names.


I've been looking around how to convert big-endian to little-endians. But I didn't find any good that could solve my problem. It seem to be there's many way you can do this conversion. Anyway this following code works ok in a big-endian system. But how should I write a conversion function so it will work on little-endian system as well?  This is a homework, but it just an extra since the systems at school running big-endian system. It's just that I got curious and wanted to make it work on my home computer also  #include <iostream> #include <fstream>  using namespace std;  int main() {    ifstream file;     file.open("file.bin", ios::in | ios::binary);     if(!file)       cerr << "Not able to read" << endl;    else    {       cout << "Opened" << endl;        int i_var;       double d_var;        while(!file.eof())       {          file.read( reinterpret_cast<char*>(&i_var) , sizeof(int) );          file.read( reinterpret_cast<char*>(&d_var) , sizeof(double) );          cout << i_var << " " << d_var << endl;       }    }    return 0; }   Solved  So Big-endian VS Little-endian is just a reverse order of the bytes. This function i wrote seem to serve my purpose anyway. I added it here in case someone else would need it in future. This is for double only though, for integer either use the function torak suggested or you can modify this code by making it swap 4 bytes only.  double swap(double d) {    double a;    unsigned char *dst = (unsigned char *)&a;    unsigned char *src = (unsigned char *)&d;     dst[0] = src[7];    dst[1] = src[6];    dst[2] = src[5];    dst[3] = src[4];    dst[4] = src[3];    dst[5] = src[2];    dst[6] = src[1];    dst[7] = src[0];     return a; }

How do I convert between big-endian and little-endian values in C++? For clarity, I have to translate binary data (double-precision floating point values and 32-bit and 64-bit integers) from one CPU architecture to another.  This doesn't involve networking, so ntoh() and similar functions won't work here.  Note: The answer I accepted applies directly to compilers I'm targeting (which is why I chose it).  However, there are other very good, more portable answers here.


I use Ubuntu 16.04. APT cannot seem to find the package m4:  root@kevin:/# sudo apt install m4  Reading package lists... Done Building dependency tree        Reading state information... Done Package m4 is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'm4' has no installation candidate   I ran:  sudo apt-get upgrade && apt-get update   This didn't make any difference.  root@kevin:/# grep main /etc/apt/sources.list # deb cdrom:[Ubuntu 16.04.3 LTS _Xenial Xerus_ - Release amd64 (20170801)]/ xenial main restricted # deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial main restricted # deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-updates main restricted ## extensively as that contained in the main release, although it includes # deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse # deb-src http://security.ubuntu.com/ubuntu xenial-security main restricted

There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.


Is that possible in SOQL to concatenate two fields?  SELECT id,name,Description, Make__r.Name + '  ' +            Model__r.Name + ' ' + Model_Year__c  FROM my_custom_object__c

I am trying to run SOQL statement in salesforce.schema tool of FORCE.COM the following query:  Select c.LastName, c.FirstName From Contact c WHERE (FirstName+' '+LastName) In ('Good Name','Bad Name')   It produces an error.   Can I do this kind of things with SOQL ? If yes, then how I can concatenate fields in the query ?


I have this table:  CREATE TABLE `test` (   `Id1` int(11) unsigned NOT NULL,   `Id2` int(11) unsigned NOT NULL,   `Id3` int(11) unsigned NOT NULL,   `Id4` int(11) unsigned NOT NULL AUTO_INCREMENT,   `Name` varchar(255) NOT NULL,   PRIMARY KEY (`Id1`,`Id2`,`Id3`,`Id4`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ROW_FORMAT=DYNAMIC;  INSERT INTO `test` (`Id1`, `Id2`, `Id3`, `Name`) VALUES (1, 1, 1, 'test') INSERT INTO `test` (`Id1`, `Id2`, `Id3`, `Name`) VALUES (1, 1, 1, 'test2') INSERT INTO `test` (`Id1`, `Id2`, `Id3`, `Name`) VALUES (1, 2, 1, 'test') INSERT INTO `test` (`Id1`, `Id2`, `Id3`, `Name`) VALUES (1, 2, 1, 'test2')   After creating the table the date looks like this:  Id1   Id2   Id3   Id4   Name  1     1     1     1     test 1     1     1     2     test2 1     2     1     1     test 1     2     1     2     test2   Id4 is incrementing as is expected but I have problem to get inserted Id4 using PHP mysqli. This is the code I am using:  $db = new mysqli('host', 'user', 'pass', 'db'); $db->query("INSERT INTO `test` (`Id1`, `Id2`, `Id3`, `Name`) VALUES (1, 1, 1, 'test')"); var_dump($db->insert_id);   I get result  int(0)   Result should be int(1) but I get zero for no reason. Any ideas?

Can I get the LAST INSERT ID() for a compound key in MySQL?


This was originally noticed  but some quick checks show that this is not an issue exclusive to GD.SE. It occurs in both questions and .  Here's a Demonstration:   List             Image credit

A   B   C   D   E   F             I don't even know. It just seemed weird.  Yes, I understand I could just avoid doing something like that. But the problem already exists with a single level.   Consider having 2 images in a post. Both exceed the maximum width of a post. One is nested in a list. Key to this issue is that my original images were much larger. They were automatically resized.  Image    List      I think it looks weird.


I'm using winforms with xna. Everything's working so far except for the drawing because invalidate won't refresh the screen unless repeated. This is the initial code I had:           protected override void Draw()         {             GraphicsDevice.Clear(Color.CornflowerBlue);             spriteBatch.Begin();             tileSheet.Draw(spriteBatch);             foreach (Image img in selector)                 img.Draw(spriteBatch);             spriteBatch.End();         }   I placed a breakpoint and it is calling the draw method but nothing is changing on the screen but when I do this:   protected override void Draw()     {         GraphicsDevice.Clear(Color.CornflowerBlue);         spriteBatch.Begin();         tileSheet.Draw(spriteBatch);         foreach (Image img in selector)             img.Draw(spriteBatch);         spriteBatch.End();          Invalidate();     }   It works! but the problem is that everything gets frozen and it seems to get caught up in an Invalidate loop. But why does the latter work but not to former? I've been working at this for hours now and I can't understand what's going wrong :/.   I feel like it's something simple but I can't wrap my head around it.   ps. I've also tried Update and Refresh and they don't work either.

I'm using the Winforms sample on the app hub and everything is working fine except my spritebatch won't draw anything unless I call Invalidate in the Draw method. I have this in my initialize method:   Application.Idle += delegate { Invalidate(); };    I used a breakpoint and it is indeed invalidating my program and it is calling my draw method. I get no errors with the spritebatch and all the textures are loaded I just don't see anything  on the screen. Here's the code I have:      protected override void Draw()     {         GraphicsDevice.Clear(Color.CornflowerBlue);         spriteBatch.Begin();         tileSheet.Draw(spriteBatch);         foreach (Image img in selector)             img.Draw(spriteBatch);         spriteBatch.End();     }   But when I do this:       protected override void Draw()     {         GraphicsDevice.Clear(Color.CornflowerBlue);         spriteBatch.Begin();         tileSheet.Draw(spriteBatch);         foreach (Image img in selector)             img.Draw(spriteBatch);         spriteBatch.End();         Invalidate();     }   then all of a sudden the drawing starts to work! but the problem is that it freezes everything else and only that control gets updated. What can I do to fix this? It's really frustrating.


I  have tried to install LAMP on Ubuntu 14.04LTS Cant get PHPmyAdmin to work and access MYSQL Where is the clearest set of instructions to install LAMP

I set up a new VPS instance of Ubuntu and am wondering what the easiest way is to get up and running with a basic LAMP stack (i.e. which packages are required, which configuration options need to be tweaked, if any, etc.).


I'm posting this question because normally he is a very punctual person, often responding within a matter of hours if our time zones match up. However, I sent an email last week and a follow-up one on Sunday, and he has yet to read it (according to my email-tracking software).   I don't think his university has started break yet, so should I wait a little bit and leave a message?   Edit: Question should not be considered a duplicate because I am inquiring as to whether I should call him now that email seems to be "exhausted" so to speak, but I'm not sure if calling is appropriate.

I have sent  an email to a professor at a local university. The email asks for assistance with a fairly large science fair. I have done much of the work and the email was asking about how I could improve it.  After 4 days I have not received a response yet.  Usually people check their email on a fairly regular basis (Once a day, usually) and so I am naturally worried about it.   Is it possible the professor has not read the email yet or should I email other professors?


Prove that the invariant factors of $\mathbb Z_m\times\mathbb Z_n$ are $mn$ if $m$ and $n$ are relatively prime and are the greatest common divisor and the least common multiple of $m$ and $n$ if they are not relatively prime.

How would one go about proving that $\mathbb{Z}_m\oplus \mathbb{Z}_n \cong \mathbb{Z}_d\oplus \mathbb{Z}_l $ as groups, where  $l=\mathrm{lcm}(m,n)$ and $d=\gcd(m,n)$?    I am attempting to use the fundamental theorem of finitely generated abelian groups but am struggling. In the interest of honesty, this is a past exam question that I am attempting for which the solutions are not available. EDIT: As the question was asked in the paper, the Chinese Remainder Theorem would not be permitted since this is only proved in the follow-up course.


Could you please explain the reason for the difference in use between "it" and "that?"  Example:     A.  Is your name Jim?  B. Yes, it is.     We can't say "Yes, that is". Why not?     B.  Is your name Jim?  B. Yes, that's right, it is.     We can't say "Yes, it's right".  Why not?

Consider the following exchange:  [1] Q: Is your name Jane?      Aa: *Yes, it's right.      Ab: Yes, that's right.  Note that [1Aa] is simply not acceptable. It's not just that that is preferred to it; it's rather that, in Standard English, it simply cannot be used here.  Why not?   Yes, in the replies [1A], the reference is clearly (supposed to be) deictic rather than anaphoric (see below); and the characteristic usage of 3rd person personal pronouns he/she/it/they is anaphoric. But they certainly can function deictically at least sometimes;  gives the following example (p. 1469): Isn't she lovely! (uttered while looking at someone's baby).  So why is [1Aa] completely unacceptable, rather than just being less favored than [1Ab]?  I am well aware that Yes, it is would be completely acceptable... and I do understand why it would be. But [1Aa] is not, and my question is specifically about why it is not.  Some background on deixis  [1Ab] is a clear example of deictic use of that, very much like the [27ii] example from CGEL (p. 1461):     [27] i A: Kim has been falsifying the accounts. B: That's   terrible. [anaphoric]       ii A: Kim   has been falsifying the accounts. B: That's a lie.   [discourse-deictic]       In [i] A's utterance is the antecedent for B's that, which refers to   the situation that A has  described. But in [ii] that refers to A's   speech act, to a linguistic entity in the prior discourse.


I want to add some points that represent coordinates (in shapefile) onto geotiff image which is earth basically. I used command line:  gdal_rasterize -burn 200 -ts 1000 600 -ot byte -l point point.shp land.tiff   but this just gave me a black backgrounded image with red dots. I'm new with gdal and gis so maybe my way could be a little bit wrong. Maybe ı should use gdal_grid but ı don't know how

I have an ASCII file with latitude, longitude, and data_val in the following format.  35-13.643782N, 080-57.190157W, 118.6 ...   I have a GeoTiff image file, and I can easily view it.  I want to place a "pin" (can be a dot/flag/star or whatever is easiest) on the image at the specific latitude/longitude position found in the ASCII file.  Here is what I've managed to do so far:  My source image looks like this:  Driver: GTiff/GeoTIFF Files: /tmp/Charlotte SEC 100.tif Size is 16867, 12358 Coordinate System is: PROJCS["Lambert Conformal Conic",     GEOGCS["NAD83",         DATUM["North_American_Datum_1983",             SPHEROID["GRS 1980",6378137,298.2572221010042,                 AUTHORITY["EPSG","7019"]],             AUTHORITY["EPSG","6269"]],         PRIMEM["Greenwich",0],         UNIT["degree",0.0174532925199433],         AUTHORITY["EPSG","4269"]],     PROJECTION["Lambert_Conformal_Conic_2SP"],     PARAMETER["standard_parallel_1",38.66666666666666],     PARAMETER["standard_parallel_2",33.33333333333334],     PARAMETER["latitude_of_origin",34.11666666666667],     PARAMETER["central_meridian",-78.75],     PARAMETER["false_easting",0],     PARAMETER["false_northing",0],     UNIT["metre",1,         AUTHORITY["EPSG","9001"]]] Origin = (-365041.822331817995291,240536.419747152860509) Pixel Size = (42.334586069440391,-42.334898968590878) Metadata:   AREA_OR_POINT=Area   TIFFTAG_DATETIME=2016:06:24 12:46:45   TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)   TIFFTAG_SOFTWARE=Adobe Photoshop CS5 Windows   TIFFTAG_XRESOLUTION=300   TIFFTAG_YRESOLUTION=300 Image Structure Metadata:   COMPRESSION=LZW   INTERLEAVE=BAND Corner Coordinates: Upper Left  ( -365041.822,  240536.420) ( 82d48'55.43"W, 36d13' 4.92"N) Lower Left  ( -365041.822, -282638.262) ( 82d35'10.11"W, 31d30'17.00"N) Upper Right (  349015.641,  240536.420) ( 74d51'46.40"W, 36d13'26.16"N) Lower Right (  349015.641, -282638.262) ( 75d 4'55.60"W, 31d30'36.99"N) Center      (   -8013.091,  -21050.921) ( 78d50'12.11"W, 33d55'36.35"N) Band 1 Block=16867x1 Type=Byte, ColorInterp=Palette   Color Table (RGB with 256 entries)     0: 255,255,255,255 ...   Here is what I've managed to cobble together in Python:  from osgeo import gdal, osr  src_filename = '/tmp/Charlotte SEC 100.tif' dst_filename = '/tmp/foo.tiff'  # Opens source dataset src_ds = gdal.Open(src_filename) format = "GTiff" driver = gdal.GetDriverByName(format)  # Open destination dataset dst_ds = driver.CreateCopy(dst_filename, src_ds, 0)  # Specify raster location through geotransform array # (upperleftx, scalex, skewx, upperlefty, skewy, scaley) # Scale = size of one pixel in units of raster projection # this example below assumes 100x100 gt = [-365041.822, 100, 0, 240536.420, 0, -100]  # Set location dst_ds.SetGeoTransform(gt)  # Get raster projection epsg = 4269            # http://spatialreference.org/ref/sr-org/lambert_conformal_conic_2sp/ srs = osr.SpatialReference() srs.ImportFromEPSG(epsg) dest_wkt = srs.ExportToWkt()  # Set projection dst_ds.SetProjection(dest_wkt)  # Close files dst_ds = None src_ds = None   But, I can't quite figure out how to place a "red dot" at 35-13.643782N, 080-57.190157W  I'm having to learn some new details here (nomenclature about GIS).


Within several sci-fi universes (Star Wars and Star Trek in particular), when a ship jumps to FTL speeds, it's to traverse across galaxies. But is there anything that says you must travel a certain distance in order for whatever specific device it is that powers FTL travel to work? In other words, will the drives allow FTL to a neighboring planet or a location inside the same solar system?  As previously stated, I'm only asking if Star Wars and/or Star Trek have ever addressed this inside their respective worlds, as I'm sure there are countless other examples. Also note that I'm asking specifically about the FTL device's limitations, and not about any one captain or group's protocol (unless they actually modified the drive to act a certain way I guess).  Canonicity is not an issue.

The  basically boils down to: "surprise your enemy by jumping right next to him and unload all your cannons". However, Trek canon makes a bit more of a technological fuss about how it works.  Seeing that the Star Wars universe also has FTL travel, I wondered if:   the Picard Maneuver would be technically possible in SW and  if there are any references (probably by a different name) in the SW universe.


I have stumbled upon this predicate logic sequent which I have trouble proving using natural deduction: $(\forall x\ Q(x))\to P ⊢ \exists x (Q(x)\to P)$ I started with ∀xQ(x) → P as the premise. I wanted to start using universal elimination but since the ∀x doesn't cover Q(x) → P completely, I refrained from doing so. I had to assume ∀xQ(x) but when I did, I couldn't reach ∃x(Q(x) → P) out of the assumption's scope. I have also tried proof by contradiction but I couldn't progress. I tried to prove p → q ⊢ (¬p V q) with natural deduction to be able to incorporate it into the solution, but I couldn't prove it either. So, I think I am completely stuck this one. Could you help me prove this (or tell me if this cannot be proved by natural deduction for any reason)? If it helps, I am using the inference rules listed under

I couldn't find a proper answer. I am pretty sure the universal quantifier elimination rule can't be applied directly and I tried proving by contradiction, but couldn't complete it.


I currently have a Live USB with Ubuntu 12.04 on it and my Laptop is a Windows 10 machine.  I would like to remove Ubuntu 12.04 and use Tails instead. The reason I want to use Tails is that I am planning on storing my Cryptocurrency Wallets on Tails and tails is recommended for this due it having Electrum.   If Tails is not necessary for this can you please let me know how I can upgrade to the latest version of Ubuntu safely without damaging my Windows 10 OS.  Thank you

What are the different ways I can use to upgrade Ubuntu from one release to another?


I see variables defined with this type but I don't know where it comes from, nor what is its purpose. Why not use int or unsigned int? (What about other "similar" types? Void_t, etc).

In several C++ examples I see a use of the type size_t where I would have used a simple int. What's the difference, and why size_t should be better?


I have been looking a bit around for a way to retrieve the phone number of an iOS device but without too much sucess as I've seen mixed reports  According to this link it's a no :   Also here  I don't see any information about the phoneNumber for iOS.  However, as these links aren't brand new, I would like know if things have changed since

Is there any way to get own phone number by standard APIs from iPhone SDK?


Suppose there are these classes:  class A     {         public string someField="something";             public void MethodA(){}      }  class B {     public A propertyA; }  class C {     public B propertyB;     string s1 = "propertyB.propertyA.MethodA()";             string s2 = "propertyB.propertyA.someField";     public void Method()     {         //so for s1 it does         propertyB.propertyA.MethodA();         //and for s2 it does         var something = propertyB.propertyA.someField;         //or         propertyB.propertyA.someField = "somethingNew"     } }   How can I execute a method in class A from class C represented as string s1 and get or assign value to someField(s2)?

I would like to do the equivalent of:  object result = Eval("1 + 3"); string now    = Eval("System.DateTime.Now().ToString()") as string   Following Biri s , I got this snippet (modified to remove obsolete method ICodeCompiler.CreateCompiler():  private object Eval(string sExpression) {     CSharpCodeProvider c = new CSharpCodeProvider();     CompilerParameters cp = new CompilerParameters();      cp.ReferencedAssemblies.Add("system.dll");      cp.CompilerOptions = "/t:library";     cp.GenerateInMemory = true;      StringBuilder sb = new StringBuilder("");     sb.Append("using System;\n");      sb.Append("namespace CSCodeEvaler{ \n");     sb.Append("public class CSCodeEvaler{ \n");     sb.Append("public object EvalCode(){\n");     sb.Append("return " + sExpression + "; \n");     sb.Append("} \n");     sb.Append("} \n");     sb.Append("}\n");      CompilerResults cr = c.CompileAssemblyFromSource(cp, sb.ToString());     if (cr.Errors.Count > 0)     {         throw new InvalidExpressionException(             string.Format("Error ({0}) evaluating: {1}",              cr.Errors[0].ErrorText, sExpression));     }      System.Reflection.Assembly a = cr.CompiledAssembly;     object o = a.CreateInstance("CSCodeEvaler.CSCodeEvaler");      Type t = o.GetType();     MethodInfo mi = t.GetMethod("EvalCode");      object s = mi.Invoke(o, null);     return s;  }


Let $p$ be a prime and let $d$ be a positive integer. Does there always exist an irreducible (i.e. unfactorable) polynomial of degree $d$ over $\mathbb{Z}/p\mathbb{Z}$?

I know that for every $n\in\mathbb{N}$, $n\ge 1$, there exists $p(x)\in\mathbb{F}_p[x]$ s.t. $\deg p(x)=n$ and $p(x)$ is irreducible over $\mathbb{F}_p$.     I am interested in counting how many such $p(x)$ there exist (that is, given $n\in\mathbb{N}$, $n\ge 1$, how many irreducible polynomials of degree $n$ exist over $\mathbb{F}_p$).   I don't have a counting strategy and I don't expect a closed formula, but maybe we can find something like "there exist $X$ irreducible polynomials of degree $n$ where $X$ is the number of...".  What are your thoughts ?


In the middle of the episode "Eye of the Beholder" (from the seventh season of Star Trek: The Next Generation) one of the crew members says to Troi and Worf that [no direct cite] the entire ship was built by people at Utopia Planitia. There were people virtually everywhere and he recalls himself placing some cord "right beyond that panel".  It is the 24th Century, right? Currently, four hundred years before that time, we have fully automated plants, that are able to produce most of a car, ship or plane, if not entire ones, with little or no help from human efforts. How can we imagine (taking today's progress of science as a base), that in the 24th century ships will be built using human power mostly or only? How can we believe that after the next four hundred years someone will be manually placing a cord somewhere?  Automated production lines and using pure robotic sections in plants are not a 21st Century discovery. There were available (at least in the automobile industry) back in the early 1980s, if not earlier. Star Trek: The Next Generation writers and producers must have known this.  Is there any in-universe or out-of-universe explanation as to why they decided to push this matter to a level where it becomes hard to believe, i.e. that 24th Century ships are built by hand and by human power?  This question is related to "", but only in the context of robotic machines designed to automate or aid in production and building processes — not about full-featured androids intended to replace (biological) human engineering crews.

In Star Trek, it seems like they take forever to build ships.  It takes months, if not years to make them.  So why not just build gigantic replicators in space, then replicate the ship (excepting non-replicatable objects like the warp core)?  This would presumably come with a huge energy cost, but would save massive amounts of time.


I imported FEMA's Advisory Base Flood Elevation (ABFE) layer. It is an ArcGIS Web Service over the internet.  I can view it on the map, but it is listed as not selectable, and I cannot export sub layers, and I cannot view the attributes table.  It seems to be locked somehow.  I need to convert this layer into a standard layer that I can clip and manipulate.

Looking at this information page for a dataset hosted on esri.com:   Trying to figure out how I can get access to the raw data (either raw lat/lng coordinates or SHP).  It looks like the data is available, I just can't figure out how to pull it from this interface.


I'll be using a momentary push button, SW1 as shown in the figure. With that, I also decided to make a D flip-flop act like a latch by connecting the switch to the clock.  My question is if my pull-down resistor value is correct. I'll be using 74LS DIP IC gate specifically . According to the data sheet, the Vil is about 0.8V while the Iil for the clock input is 0.4mA. Based on my readings in forums, I divided the two resulting to 2KΩ.  Should I aim for 2KΩ or should I use a higher or lower value for the pull-down. Sorry I'm not very familiar with this topic.          – Schematic created using

I would like to use a pull-down resistor on the input of a NOT logic gate. I am using a 5V microcontroller, and I want to ensure that the input of the gate will never be floating (eg. microcontroller damage).  General information:  The logic gate I am using is a HD74LS04 inverter whose datasheet can be found . I am testing the output by placing my positive multi-meter lead on R4 and the negative lead on GND. With the digital pin floating, the output of 1Y is 4.33V. This is the expected behavior.  The logic gate requires a minimum of 2.0V for Vih. If I understand this circuit correctly, I expect the voltage at pin 1A to be 3.76V since R2 and R3 will form a voltage divider. This value seems plenty to signify a 'high' in the logic gate.  R2 exists to protect the digital pin. Ideally, I would have liked R2 to be 1KΩ. Increasing the value of R2 means I have to increase the value of R3 to maintain the same voltage divider. During testing I found that if R3 was any value over 3.3KΩ, the pin 1A would not get pulled down all the way if I left the digital pin floating.   Tests: If I disconnect everything except GND and Vcc and place the positive lead of my multi-meter on pin 1A (now floating) and the negative lead to GND, I read 1.49V. Placing a pull-down resistor (R3) on pin 1A to GND with a value of 100Ω changes the reading to 0.02V. Increasing the resistor's value to 330Ω increases the reading to 0.07V. At the value I need, 3.3KΩ, the reading increases to 0.60V. Finally, changing the resistor's value to 1MΩ increases the reading to 1.47V and actually changes the output of pin 1Y to low.  The test that uses the 3.3KΩ resistor is concerning. The reading I took (0.60V) seems to be approaching the Vil maximum of the logic gate which is 0.80V.   Questions:  This must be a trivial question, but why does an R3 value of 3.3KΩ not pull pin 1A all the way to GND? Is there a formula for determining the correct pull-down resistor value? Other answers I found on here simply state 10KΩ as a 'good' value for a pull-up resistor. I'm not sure where that value comes from or if it is applicable to a pull-down resistor.         – Schematic created using   Edit: Although Ignacio's answer technically answers the question, I thought I would share some information I found for others who may come across this question.  User 'Papabravo' on the  states that the calculation for a pull down resistor can be calculated by taking the Vil (0.8V) and dividing it by the "standard TTL load" of 1.6mA. As Ignacio pointed out, my specific logic gate can source up to 0.4mA, so the calculation would be 0.8/0.0004A which equals 2KΩ. For safety, I performed the calculation at 0.5V in order to give myself some headroom.  Other Resources: