For some reason, the Generic USB Keyboard driver was removed, literally, over night, from Windows.  Can someone that has Windows 7 and uses a USB Keyboard without any fancy drivers (i.e. uses Generic Windows USB Keyboard driver) go to  Device Manager>Keyboards>USB Keyboard>Properties>Driver>Driver Details   and post the name of the driver system files (for example  "C:\Windows\system32\DRIVER\i8042prt.sys")?

I got two laptops which share keyboard, mouse and monitor using a kvm-switch. One laptop runs Windows XP and works perfectly. The other one running Windows 7, however does not recognize keyboard and mouse.  I made the hidden devices visible and deleted the unused ones. After the reboot the keyboard and the mouse work. Windows 7 tries to find the 'missing' drivers and upon failing deactivates the devices which renders them unusable again.  Has anybody had the same problem and can help me with it?  Cheers, AC  Edit:  The KVM-Switch is an ATEN Petite CS692 2-Port USB HDMI KVM Switch  The keyboard a standard 102-key Logitech USB  The mouse a Logitech M705 Marathon Mouse with an unify[sic?] connector.  No adapters for the keyboard or mouse but one for dvi to hdmi on the Windows XP machine.


like the title already says, I´m looking for a possibility to create own document templates containing all the relevant document class, package and formatting information. Since I´m often using the same or very similar preambles, it would be much easier to just select a template instead of typing everything or copying the preamble from an existing document everytime I want to create a new one.  Is there any possibility to do that? I am using Texmaker as editor.  Thanks a lot in advance. :)

How can I create a template using TeXmaker? I would create a default file and use it every time I need to make a new LaTeX file.  For example using MS Word it's possible save a document as model and use it every time I need it. Is it possible also in TeXmaker?


Context for the question: According to , ARG_MAX is maximum length of command-line arguments to exec() family of functions. Which lead me to believe that's actual number of arguments, however that clearly didn't work:  $ ulimit -s 8192 $ touch {1..18000}.jpg $ rm *.jpg $    Clearly, this works fine, despite being in length over 8192 items. According to , the 8192 is supposedly size in kB. So clearly the previous assumption was wrong.   This is where the actual question comes in: How do I figure out the amount of items that actually will get above 8192 kB limit ? In other words, what sort of computation I have to perform to ensure that *.jpg type of glob will result into Argument list too long error ?  Please note, this isn't a duplicate of . I know about getconf ARG_MAX and ulimit -s values, that's not my question. I need to know how to generate enough arguments in size that will be above the limit. In other words, I need to find a way to get the error, not avoid it.

I was under the impression that the maximum length of a single argument was not the problem here so much as the total size of the overall argument array plus the size of the environment, which is limited to ARG_MAX. Thus I thought that something like the following would succeed:  env_size=$(cat /proc/$$/environ | wc -c) (( arg_size = $(getconf ARG_MAX) - $env_size - 100 )) /bin/echo $(tr -dc [:alnum:] </dev/urandom | head -c $arg_size) >/dev/null   With the - 100 being more than enough to account for the difference between the size of the environment in the shell and the echo process. Instead I got the error:  bash: /bin/echo: Argument list too long   After playing around for a while, I found that the maximum  was a full hex order of magnitude smaller:  /bin/echo \   $(tr -dc [:alnum:] </dev/urandom | head -c $(($(getconf ARG_MAX)/16-1))) \   >/dev/null   When the minus one is removed, the error returns. Seemingly the maximum for a single argument is actually ARG_MAX/16 and the -1 accounts for the null byte placed at the end of the string in the argument array.  Another issue is that when the argument is repeated, the total size of the argument array can be closer to ARG_MAX, but still not quite there:  args=( $(tr -dc [:alnum:] </dev/urandom | head -c $(($(getconf ARG_MAX)/16-1))) ) for x in {1..14}; do   args+=( ${args[0]} ) done  /bin/echo "${args[@]}" "${args[0]:6534}" >/dev/null   Using "${args[0]:6533}" here makes the last argument 1 byte longer and gives the Argument list too long error. This difference is unlikely to be accounted for by the size of the environment given:  $ cat /proc/$$/environ | wc -c 1045   Questions:   Is this correct behaviour, or is there a bug somewhere? If not, is this behaviour documented anywhere? Is there another parameter which defines the maximum for a single argument? Is this behaviour limited to Linux (or even particular versions of such)? What accounts for the additional ~5KB discrepancy between the actual maximum size of the argument array plus the approximate size of the environment and ARG_MAX?   Additional info:  uname -a Linux graeme-rock 3.13-1-amd64 #1 SMP Debian 3.13.5-1 (2014-03-04) x86_64 GNU/Linux


The usual answer to the twin paradox is that the twin who undergoes acceleration is the one who finds the other has aged more, because the trajectory of the 'travelling twin' does not amount to a single inertial frame - the travelling twin has accelerated while the stationary twin has not. But isn't acceleration a relative phenomenon? If the universe were empty apart from the two twins, what does it mean to say that one and not the other is accelerating and how could it be decided which was which?  (Inevitably someone will say this is a duplicate - apologies if so but I can't find it)  Edit: thank you for those thoughtful responses - on reflection I was asking two questions and the twin paradox is about velocity not acceleration. I think the interesting question is how we distinguish the velocities or accelerations of two objects, which you need to do in order to calculate the proper time elapsed for each. It can't be enough to say that the accelerating one 'feels it' - that is true only insofar as the force is transmitted from one part of the object to another (such as from the rocketeer's back against the seat to her inner ear, or from the body of the accelerometer on the floor of the rocket to its detector component). Maybe it relates to Mach's conjecture about absolute rotation, ie that you have to make reference to the distribution of matter in the wider universe in order for the distinction of moving vs not moving to have meaning. If so there is a sense in which acceleration is relative rather than absolute. Anyway thank you.

Suppose a box A is moving relative to a Box B, then by time dilation equation if I take 1 sec passed for an observer in A then for an observer in B will be little longer. Now if I suppose that the box B is moving while A is stationary under the same condition, then by the time dilation equation time passed in B must be shorter than A. How is this issue resolved? In the twin paradox problem my book says that it's due to acceleration, but in my opinion acceleration is relative (please correct me if I'm wrong), but here it is not the case.


Let $G$ be a finite group. Prove G is cyclic if  for every $n\in \Bbb{N}$, there are at most $n$ solutions to the equation $x^n=e$.    I am stuck with this :( Would appreciate your help.

Fraleigh(7th ed) Sec10, Ex47. Let $G$ be a finite group. Show that if for each positive integer $m$ the number of solutions $x$ of the equation $x^m=e$ in $G$ is at most $m$, then $G$ is cyclic.   I tried it a few hours but I couldn't solve it. So I read the solution. But I narrowly understood the solution, and it's still unclear to me. How can I solve it?


I'm a new GM and am running a game with new players. I'm helping them make first-level characters. One player's bard has a −1 wisdom modifier and proficiency in perception (a wisdom-based skill). At first level, her proficiency bonus is +2. Does she have a +1 perception bonus or should I ignore the negative and give her +2 because she is proficient in that skill?

I'm trying to fill out the skills section on my first character, but when I look at the character sheets in the Starter Set as examples of how to make a character, the skills that are circled have higher modifiers than their Dexterity or Strength or whatever should make them.  I've filled out all skills but those. What do I add to the ability modifier to get those numbers?   My abilities are Strength 13, Dexterity 14, Constitution 11, Intelligence 15, Wisdom 8, and Charisma 8. Proficiencies are Arcana, Athletics, History, Investigation and Stealth. My saving throws are Strength and Dexterity.   I just started D&D and have the Player's Handbook, DM's Guide, Monster Manual, and the Starter Set.


I want to write text like this, where the word circumference should come under the word When.

Theorem: When a quadrilateral is inscribed in a cycle i.e. the vertices of the quadrilateral lie on the           circumference of a circle; the quadrilateral is called a cyclic quadrilateral.  lala: xxxx lala lala       yyyy   Question: How to have yyyy below xxxx?


I am trying to find a formula which will search one cell for specific words.   I would like the outcome of the formula to be words I have selected.  The example of this I have is if one cell shows the list of ingredients, and the other cell shows a list of allergens. I need the formula to search the list of ingredients and choose the allergens.    I know that I could use the find function so that it came back with one result and then concatenate the results but there must be a more simple way!  Thanks

I am no expert with excel so any help is appreciated!   I am trying to make one cell do multiple searches within another.  I know that to search one cell for a specific word you would use  =FIND(Blue,C2)   But I need to find multiple different words in one cell. Heres an example of what im trying to do:    I need to show all the allergens in the ingredients cell eg peanuts, gluten, milk, sesame seeds etc   How do I get the result to list all the allergens?   I know that I can do a single find function in separate cells and then concatenate them, but there must be a more simple way?  Thanks


I'm not in Adventure Mode, but I must use the right tools to destroy blocks. It does it at some points while I am playing, and then it stays like that and don't know why. Does anyone know what i am on about?

I'm playing on a Survival world with cheats on, "easy" difficulty, and at night in-game. I didn't have a sword or anything to make a sword with, and I was starving, so I switched to Creative to give myself a stack of food and a bed to set my spawn point. When I switched back to Survival, I couldn't destroy or place blocks. I'm on single player, and my Internet is fine, and I can destroy blocks still if I switch to creative. I've tried resetting the button one, and reloading the map, and it still doesn't work. I've even tried deleting everything I gave myself in Creative. This happened before on a different world and I ended up deleting it.  This only happens on this world. How do I fix it?  If I know I'm in the correct game mode, what else can cause this?  Are there different causes in multiplayer?


For example, if I have a dweller with max Perception (level 10) and I give him/her armor that boosts Perception by 3. Is his/her Perception level then counted as 13 or is it capped at 10?

We know that the maximum level a dweller can train to on any SPECIAL skill is 10, however this does not consider bonuses given from their outfit.    Is there any additional benefit for going over 10? For example, a dweller with an Intelligence skill of 10 wearing a lab coat that boosts Intelligence by 3?   If it is a hard cap, would it be more useful to use outfits that raise a secondary characteristic instead?


I need to create a function for sending newsletters everyday from crontab. I've found two ways of doing this on the internet :  First - file placed in the django project folder:  #! /usr/bin/env python import sys import os  from django.core.management import setup_environ import settings setup_environ(settings)  from django.core.mail import send_mail from project.newsletter.models import Newsletter, Address  def main(argv=None):     if argv is None:         argv = sys.argv      newsletters = Newsletter.objects.filter(sent=False)     message = 'Your newsletter.'      adr = Address.objects.all()     for a in adr:         for n in newsletters:             send_mail('System report',message, a ,['user@example.com'])  if __name__ == '__main__':     main()   I'm not sure if it will work and I'm not sure how to run it. Let's say it's called run.py, so should I call it in cron with 0 0 * * * python /path/to/project/run.py  ?  Second solution - create my send function anywhere (just like a normal django function), and then create a run.py script :  import sys import os  os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'  module_name = sys.argv[1] function_name = ' '.join(sys.argv[2:])  exec('import %s' % module_name) exec('%s.%s' % (module_name, function_name))   And then in cron call : 0 0 * * * python /path/to/project/run.py newsletter.views daily_job()  Which method will work, or which is better ?

I've been working on a web app using Django, and I'm curious if there is a way to schedule a job to run periodically.   Basically I just want to run through the database and make some calculations/updates on an automatic, regular basis, but I can't seem to find any documentation on doing this.  Does anyone know how to set this up?  To clarify:  I know I can set up a cron job to do this, but I'm curious if there is some feature in Django that provides this functionality.   I'd like people to be able to deploy this app themselves without having to do much config (preferably zero).  I've considered triggering these actions "retroactively" by simply checking if a job should have been run since the last time a request was sent to the site, but I'm hoping for something a bit cleaner.


The tuptime command help to find system uptime and other information easily. tuptime -d has date option to find daily uptime or past date uptime. How to find past time or current date system uptime based on the date For example, system working 2 hours on date 02 05 2021 then shut down and again 3 hours again shutdown Same like above system uptime for the date 15 04 2021 Any idea?

I'm a Rails developer working on a web application on Ubuntu Server 10.04. Due to internal requirements, I was asked to find the last 10 system boot and shutdown times... I have no clue where to find these details. Could someone help me out?


This is my first post after switching to Ubuntu 14.04 LTS, desktop version, for my media server.  I am having problems creating share on an extra drive.  I can create and access shares on the system drive. But I have added a 2nd drive to hold my data (will probably RAID in the near future) however when I create a share using the GUI on this drive it is inaccessible and i keep getting access denied errors. Can anyone shed any light on what i am doing wrong?  All the permission and share settings are the same. I have also tried changing the permissions on the folder containing the shared folder but this doesn't have any effect

It doesn't seem that many others have had this problem so I thought I'd ask here.  Have a server running Ubuntu with 1 internal and 1 external drive. Have a folder shared with samba on the internal drive that can be accessed, however, when sharing the entire external or just a folder on it I get the "You do not have permission to access" error on the Windows clients.   When sharing on Ubuntu I go to properties, share and then tick share, allow others to write as well as guest access. Clicking create share then says it will have to set the permissions and I let it. It's not accessible. When trying to set permissions manually in the Permissions tab it doesn't let me choose anything, when choosing Read and Write for "other" users it reverts back to nothing as soon as it's chosen.  I've tried creating a symlink from the mount point to within the home directory and sharing that, even getting chmod to change the permissions so they're viewable in ls -la, but it still isn't accessible. Is there something really simple I'm missing here like externals not being easily shared? Thinking I might have to crack it open and stuff it inside the server. Oh and the external is NTFS, if that would make a difference.


I recently got a more complete proof of photons having no mass. (I knew it before, but now I really know it.) But now, I'm curious how gravitational lensing can occur without a mass to act on.  I have heard that space is like a sheet and gravity works because the more massive an object is, the more it bends space. I heard that when I was five years old. When I got older I questioned how that would work, seeing as space is 3-dimensional. The answer I eventually cobbled together from a plethora of excellent resources was this:      Gravity is like a point light source. At the center, you have the most intense light. As you move outward the intensity decreases with the square of the distance. Like light, gravity radiates in all directions simultaneously.   This works well for me, and I still believe it to be accurate. However, when I was thinking about photons, I realized that you cannot apply a force to an object without mass. At least, you can't by standard Newtonian thinking. This is because $F=ma$. With no mass, you can have no force. Alternately, you could rearrange to $\frac{F}{m}=a$. With no mass, and no force, you can have no acceleration.  Yet gravity is able to refract light.   How is this possible? Like $E=mc^2$, does this only apply to a specific set of conditions?

I understand that a black hole bends the fabric of space time to a point that no object can escape.   I understand that light travels in a straight line along spacetime unless distorted by gravity. If spacetime is being curved by gravity then light should follow that bend in spacetime.  In Newton's Law of Universal Gravitation, the mass of both objects must be entered, but photon has no mass, why should a massless photon  be affected by gravity in by Newton's equations?  What am I missing?


You know that the printf function written in C allows to do:  printf('%2$s %2$s %1$s %1$s', 'World', 'Hello');   → Hello Hello World World  But in GNU Bash:  printf '%2$s %2$s %1$s %1$s' 'World' 'Hello'   → bash: printf: $': invalid format character  Also for /usr/bin/printf:  /usr/bin/printf '%2$s %2$s %1$s %1$s' 'World' 'Hello'   → /usr/bin/printf: %2$: invalid conversion specification  How to obtain the C behavior in Bash? Thanks.  Edited:  I was curious about this behaviour, I can't accept a workaround that changes the order of the arguments. It should work just playing with the format string.  Edited:  E.g. think about GNU Bash source code internationalization. Very improbable without this feature.

How can I refer back to arguments to coreutil's printf in no particular order?  This is what I want to avoid:  $ printf '%s %s %s %s %s %s %s' a c a c b c a a c a c b c a   This is what I would like to do:  $ printf '%s %s³ %s¹ %s³ %s² %s³ %¹' a b c a c a c b c a   This is how to do it with Perl.  perl -e 'printf ("%s %3\$s %1\$s %3\$s %2\$s %3\$s %1\$s\n", 'a', 'b', 'c');' a c a c b c a   Notice only four arguments are passed to printf.


Problem:  I have this ATK-SIM900A GSM / GPRS module which will be used to send sms. But I can't figure out how to interface it with an Arduino as there are no documentation available online.  Module Specification  ATK-SIM900A GSM/GPRS Board from Alientek    Things I've tried so far  Connection  I've tried connecting the module with Arduino in following manner  SIM900A  TX <-> Arduino RX SIM900A  RX <-> Arduino TX SIM900A GND <-> Arduino GND   I've powered up the ATK-SIM900A module with 12V-2A DC supply  Programming   Tried SoftwareSerial library  Tried a some GSM libraries and programs        What I'm doing wrong? Any kind of help will be much appreciated.   Why it isn't a duplicate of other questions:  I am working with ATK-SIM900A GSM / GPRS module, it has different features and pinout than the module asked in those questions. I've tried the solution stated in this question (), it didn't work.

I have bought an SIM900A Mini V4 GSM module. Here is the module,   I want to configure with arduino to send and receive SMS.   Do I have to connect TXD of this module--Tx of Arduino & RXD of this module--Rx of Arduino or other way around?  There is no datasheet or documents on this new module.  When I search about RXD & TXD, I found this in      TxD means "Data to be transmitted over the comms link" - which will clearly be an input to the modem;    Similarly, RxD means "Data that has been received from the comms link" - which will clearly be an output from the modem.    But I couldn't send or receive SMS using this configurations.  As I am new to this, It would be very helpful if anyone help on this.  Thank you in advance.


The page links in squares at the bottom of  are broken, as in this example:  https://stackoverflow.com/users?page=2&amp;tab=reputation&amp;filter=week   Note extra "amp;" after "&".  Actually, the links do work, but the GET attributes are lost. For instance, if you choose filter=ALL and then try to pass to page 2, you go back to default filter=WEEK.

The pagination at the bottom of the users pages uses links that have all the parameter delimiters (&) escaped to &amp;.  The  page for example, links to https://stackoverflow.com/users?page=2&amp;tab=reputation&amp;filter=all instead of to https://stackoverflow.com/users?page=2&tab=reputation&filter=all. Because of this the weekly rank, page two, is shown instead.  This is not limited to just the user pages; it appears that all pagination links are affected.    The same problem can be seen with search result pagination, this  renders the link to page 2 as https://stackoverflow.com/search?page=2&amp;tab=relevance&amp;q=python%20list%20comprehension. The second page returns no results because of this. The  tag page pagination links to https://stackoverflow.com/questions/tagged/python?page=2&amp;sort=newest&amp;pagesize=50. Page two is returned but any sorting or page size parameters are lost. Because the site uses cookies for the sort and pagesize parameters this problem is less severe. For 10k+ users, you can filter the review queue history page to show only your own reviews; when you switch that on the pagination links there are broken as well: https://stackoverflow.com/review/close/own/history?page=2&amp;userid=100297 for the close review history page, page two, filtered on my own reviews.   The footer software revision is rev 2013.8.30.981 and this problem appears to be browser independent.


Many tutorials talk about disabling secure boot before installing 17.10 over Windows 10. Sadly, I have already put 17.10 alongside an already installed Windows 10 (based on dual boot experience of Windows 7 days). I even tried EasyBCD, which shows greyed out entry when I try to add Ubuntu to boot.   Currently, the PC boots into Windows 10 as if there is no Ubuntu installed on it. Is it possible to fix this ? Please tell me how.

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


$$x^2+y^2=\frac{dy}{dx}$$  Originally, this is a question I asked on Quora.     Maybe this question has been solved but I was wondering if it can be done by integrating factor?  $$x^2=\frac{dy}{dx}-y^2$$  Using method of integrating factor  $$\text{I.F}= e^{\int-ydx}$$  $$\text{I.F}= e^{-yx}$$  Can it be done in this way?

$$y'=x^2+y^2$$ I know, that this is a kind of Riccati equation, but is it possible to solve it with only simple methods? Thank you


I had lost this computer around the house and now that I'm trying to get back onto it I have completely forgotten my login name

I'm working on a Ubuntu system, and my client has completely forgotten his administrative password. He doesn't even remember entering one; however it is there.  I've tried the suggestions on the website, and I have been unsuccessful in deleting the password so that I can download applets required for running some files. Is there a solution?


I have some confusion regarding meta-classes.  With inheritance  class AttributeInitType(object):     def __init__(self,**kwargs):        for name, value in kwargs.items():           setattr(self, name, value)  class Car(AttributeInitType):      def __init__(self,**kwargs):         super(Car, self).__init__(**kwargs)     @property     def description(self):        return "%s %s %s %s" % (self.color, self.year, self.make, self.model)  c = Car(make='Toyota', model='Prius', year=2005, color='green') print c.description   With meta class  class AttributeInitType(type):    def __call__(self, *args, **kwargs):        obj = type.__call__(self, *args)        for name, value in kwargs.items():            setattr(obj, name, value)        return obj  class Car(object):    __metaclass__ = AttributeInitType     @property    def description(self):        return "%s %s %s %s" % (self.color, self.year, self.make, self.model)   c = Car(make='Toyota', model='Prius', year=2005,color='blue') print c.description   As above example is not useful as practically but just for understanding,  I have some questions Like,   What is the difference/similarity between a meta class and inheritance? Where should one use a meta class or inheritance?

In Python, what are metaclasses and what do we use them for?


I am very keen about the fact that universe is expanding.If something expands, it expands relative to something else. If the universe is expanding, then it must expand relative to something else. What is that something else here? I am asking this question as if everything is contained in the universe itself,then where  does that something else live?

I keep hearing that universe expands. Since all is relative, the expansion must be relative to something. And since universe is all there is ... You got my point.  The only points of reference are inside the universe itself. Bonds forming, their length measured in wavelengths, etc. Red shifting of light tells us things fly away. So our point of reference is only light. (am I missing something?)  Here is my question. In a thought experiment, would it be valid to say that properties of light are somehow changing around us if we keep the size of the universe constant? If yes, what are the consequences of this line of thought? Would it give us any additional insight into what's going on?


I am trying to create a TabControl which matches the style of an existing tab control I use in WinForms, and one of the features of that is that it has tab button shapes like those found in VS (slant on the left, other edges square).  I am just starting out in WPF, so maybe I'm barking up the wrong tree, but I figured I needed to get a Border, and attach it to a Path, so that I could specify some geometry for the border... However, I just can't find any useful information. I found a 'FreeFormContentControl' class on S/O, but that is for masking content to a specific shape, rather than drawing a border around it in a specific shape.  If somebody could point me in the right direction I'd be very much obliged!

How to create trapezoid tabs in WPF tab control? I'd like to create non rectangular tabs that look like tabs in Google Chrome or like tabs in code editor of VS 2008.  Can it be done with WPF styles or it must be drawn in code?  Is there any example of code available on internet?  Edit:  There is lots of examples that show how to round corners or change colors of tabs, but I could not find any that changes geometry of tab like this two examples: VS 2008 Code Editor Tabs   Google Chrome tabs   Tabs in this two examples are not rectangles, but trapezes.


I've found some odd behavior of \bibstring{in}.  In this example, the first "in" ("in: Procedia Computer Science") is lower case, and the second is upper case ("In: Houston J. Math").  This behavior is not desired, and I have found a way to turn it off.  However, the MWE reveals what seems to my mind to be a bug in \bibstring{in}.  My guess is that the case changes because the last word in the first title is all-caps ("STEM").  But I could be wrong and am not sure where to find the defined behavior of \bibstring{in}.  I have pointedo out a workaround (insist on using capitalized verision all the time). % arara: xelatex % arara: biber % arara: xelatex % arara: xelatex \documentclass[preview]{standalone} \usepackage{biblatex} % \renewbibmacro{in:}{\printtext{In\intitlepunct}}  %% Uncomment this line to fix % \renewbibmacro{in:}{\printtext{\bibstring{in}\intitlepunct}}  %% this line doesn't work \usepackage{filecontents} \begin{filecontents}{example.bib} @article{Kohlhase2011598, title={The {P}lanetary {S}ystem: {W}eb 3.0 \& {A}ctive {D}ocuments for {S}{T}{E}{M}}, journal={Procedia Computer Science}, volume={4}, pages={598--607}, year={2011}, note={Proceedings of the International Conference on Computational Science, ICCS 2011}, issn={1877-0509}, url={http://www.sciencedirect.com/science/article/pii/S1877050911001219}, author={Kohlhase, M. and Corneli, J. and David, C. and Ginev, D. and Jucovschi, C. and Kohlhase, A. and Lange, C. and Matican, B. and Mirea, S. and Zholudev, V.}, addendum = {{\textbf{CORE: A}}; {\textbf{Google Scholar citations: 46}}}, }  @article{corneli2008double, title={Double bubbles in Gauss space and spheres}, author={Corneli, Joe and Corwin, Ivan and Hurder, Stephanie and Sesum, Vojislav and Xu, Ya and Adams, Elizabeth and Davis, Diana and Lee, Michelle and Visocchi, R and Hoffman, Neil}, journal={Houston J. Math}, volume={34}, number={1}, pages={181--204}, year={2008}, url={http://www.math.brown.edu/~diana/math/DoubleBubbles.pdf}, addendum = {{\textbf{Google Scholar citations: 16}}}, } \end{filecontents} \addbibresource{example.bib} \begin{document} \begin{itemize} \item \fullcite{Kohlhase2011598} \item \fullcite{corneli2008double} \end{itemize} \end{document}  To sum up I'm surprised that \bibstring{in} would change case depending on surrounding context.  Is this a bug?

I am using Biblatex and need to typeset full citations in my document text, so I'm using .  While it works correctly most of the time, it has trouble with Biber/BibTeX entries where the last word of a field is enclosed in braces (to force capitalization).  In these cases, \longfullcite may fail to properly capitalize the following word.  Take the following example:  \documentclass{article}  \usepackage{biblatex} \makeatletter \newcommand{\tempmaxup}[1]{\def\blx@maxcitenames{\blx@maxbibnames}#1} \makeatother \DeclareCiteCommand{\longfullcite}[\tempmaxup]   {\usebibmacro{prenote}}   {\usedriver      {\DeclareNameAlias{sortname}{default}}      {\thefield{entrytype}}}   {\multicitedelim}   {\usebibmacro{postnote}}  \usepackage{filecontents}  \begin{filecontents}{test.bib} @inproceedings{blow2015,   author       = {Blow, Joe},   title        = {{GNU} loves me},   year         = 2015,   booktitle    = {Proceedings of Some Conference}, }  @inproceedings{blow2016,   author       = {Blow, Joe},   title        = {I love {GNU}},   year         = 2016,   booktitle    = {Proceedings of Some Conference}, } \end{filecontents}  \addbibresource{test.bib}  \begin{document} \nocite{*} \noindent \longfullcite{blow2015}\\ \longfullcite{blow2016} \printbibliography \end{document}   Here is the output:    Note the inconsistent capitalization of the word "In" produced by the two \longfullcite commands.  By contrast, the citations emitted by \printbibliography correctly capitalize "In" for both entries.  What is causing this inconsistency and how can I fix or work around it (preferably by changing the definition of \longfullcite rather than changing the .bib file)?


I always thought equal signs (=), indicated double implications, however after thinking about this example, I am very confused.  For example, the Theorem (in Linear Algebra):  L($\vec{0}$) = $\vec{0}$, where L is a linear mapping can be described as:  In the equation L($\vec{x}$) = $\vec{y}$,  if $\vec{x}$ = $\vec{0}$, then $\vec{y}$ = $\vec{0}$.  However, the other implication is not true, which is if $\vec{y}$ = $\vec{0}$, then $\vec{x}$ = $\vec{0}$.  Do equals not always indicate double implications?  Thanks

Lets say for example, $L$ is a linear mapping with $V$ as its domain and $W$ as its co-domain.  Theorem: $L(0) = 0$. (Zero vectors)  I know its wrong to assume that every zero vector in $W$ is mapped from a zero vector in $V$, but I can't logically explain why!  Since $L(0) = 0$, and equal signs go both ways (double implication), isn't the statement $L(0) = 0$ implying the $0$ vector in $V$ only maps to the zero vector in $W$, and the zero vector in $W$ can be only mapped from the zero vector in $V$?  I know this is wrong. Can someone explain why?  Thanks


I'm sure this has been asked millions of times before  but I'm banging my head against a brick wall at the moment. First I will give you an overview of my goals:  I am creating a media conversion application using C# in Visual Studio 2010. I have successfully managed to convert from MP3, WAV, WMA and OGG into the AIFF file format using NAudio, however that time has come where I need to use BackgroundWorker to convert the files as the program locks up during the conversion process, and I want the progress text to be updated while they are converting. The selected media files will be in a ListView box and I use a foreach loop to run through the ListView and then convert the files individually.  The problem I am facing is accessing the ListView from a seperate thread. The error I get in debugging is:  Cross-thread operation not valid: Control 'listView1' accessed from a thread other than the thread it was created on  Here is my code to convert the files:          foreach (ListViewItem item in listView1.Items)         {             worker.ReportProgress((i * listView1.Items.Count));             if(item.Text.EndsWith(".mp3"))             {                 using (Mp3FileReader mp3 = new Mp3FileReader(item.Text))                 {                     using (WaveStream pcm = WaveFormatConversionStream.CreatePcmStream(mp3))                     {                         AiffFileWriter.CreateAiffFile(item.SubItems[2].Text, pcm);                     }                 }                 string[] saLvwItem = new string[3];                 saLvwItem[0] = item.SubItems[2].Text;                 saLvwItem[1] = "Conversion completed";                 ListViewItem lvi = new ListViewItem(saLvwItem);                 listView2.Items.Add(lvi);              }              else             {                 if (item.Text.EndsWith(".wav"))                 {                     using (WaveFileReader wav = new WaveFileReader(item.Text))                     {                         using (WaveStream pcm = WaveFormatConversionStream.CreatePcmStream(wav))                         {                             AiffFileWriter.CreateAiffFile(item.SubItems[2].Text, pcm);                         }                     }                     string[] saLvwItem = new string[3];                     saLvwItem[0] = item.SubItems[2].Text;                     saLvwItem[1] = "Conversion completed";                     ListViewItem lvi = new ListViewItem(saLvwItem);                     listView2.Items.Add(lvi);                 }                 else                 {                     if (item.Text.EndsWith(".wma"))                     {                         using (WMAFileReader wma = new WMAFileReader(item.Text))                         {                             using (WaveStream pcm = WaveFormatConversionStream.CreatePcmStream(wma))                             {                                 AiffFileWriter.CreateAiffFile(item.SubItems[2].Text, pcm);                             }                         }                         string[] saLvwItem = new string[3];                          saLvwItem[0] = item.SubItems[2].Text;                         saLvwItem[1] = "Conversion completed";                         ListViewItem lvi = new ListViewItem(saLvwItem);                         listView2.Items.Add(lvi);                     }                     else                     {                         string[] saLvwItem = new string[3];                         saLvwItem[0] = item.SubItems[2].Text;                         saLvwItem[1] = "Not converted. Unsupported format";                         ListViewItem lvi = new ListViewItem(saLvwItem);                         listView2.Items.Add(lvi);                     }                 }             }         }   Which needs to be called from the backgroundWorker1_DoWork event.  Could anyone tell me how I can get this working?  Thanks in advance...

I have a scenario. (Windows Forms, C#, .NET)   There is a main form which hosts some user control. The user control does some heavy data operation, such that if I directly call the UserControl_Load method the UI become nonresponsive for the duration for load method execution. To overcome this I load data on different thread (trying to change existing code as little as I can)   I used a background worker thread which will be loading the data and when done will notify the application that it has done its work.   Now came a real problem. All the UI (main form and its child usercontrols) was created on the primary main thread. In the LOAD method of the usercontrol I'm fetching data based on the values of some control (like textbox) on userControl.    The pseudocode would look like this:  CODE 1  UserContrl1_LoadDataMethod() {     if (textbox1.text == "MyName") // This gives exception     {         //Load data corresponding to "MyName".         //Populate a globale variable List<string> which will be binded to grid at some later stage.     } }   The Exception it gave was     Cross-thread operation not valid: Control accessed from a thread other than the thread it was created on.   To know more about this I did some googling and a suggestion came up like using the following code  CODE 2  UserContrl1_LoadDataMethod() {     if (InvokeRequired) // Line #1     {         this.Invoke(new MethodInvoker(UserContrl1_LoadDataMethod));         return;     }      if (textbox1.text == "MyName") // Now it wont give an exception     {     //Load data correspondin to "MyName"         //Populate a globale variable List<string> which will be binded to grid at some later stage     } }   BUT BUT BUT... it seems I'm back to square one. The Application again  become nonresponsive. It seems to be due to the execution of line #1 if condition. The loading task is again done by the parent thread and not the third that I spawned.  I don't know whether I perceived this right or wrong. I'm new to threading.  How do I resolve this and also what is the effect of execution of Line#1 if block?  The situation is this: I want to load data into a global variable based on the value of a control. I don't want to change the value of a control from the child thread. I'm not going to do it ever from a child thread.   So only accessing the value so that the corresponding data can be fetched from the database.


I need to somehow calculate how many a4 papers will a div on my website contain. I know that a4 paper size in pixels changes based on a screens dpi. I'm looking for a way to calculate the users screen dpi then convert it to a4 page measures in pixels and divide my div's height by that amount in order to simulate the page count using javascript or Jquery. Would that be a good way to do it or is there an alternative? And how can I know a given screens dpi (whatever it may be) and convert it to pixels?

I'm working on a kind of unique app which needs to generate images at specific resolutions according to the device they are displayed on. So the output is different on a regular Windows browser (96ppi), iPhone (163ppi), Android G1 (180ppi), and other devices. I'm wondering if there's a way to detect this automatically.  My initial research seems to say no. The only suggestion I've seen is to make an element whose width is specified as "1in" in CSS, then check its offsetWidth (see also ). Makes sense, but iPhone is lying to me with that technique, saying it's 96ppi.  Another approach might be to get the dimensions of the display in inches and then divide by the width in pixels, but I'm not sure how to do that either.


I have files like my_file.txt in my folder in ubuntu system, but when I ls on the command line terminal it shows my_file.txt~ and not my_file.txt. I need to read this file using R program which is causing it to read the file incorrectly in R. What could be the reason it show .txt~ extension in my terminal?

Why does Ubuntu create a file ending in ~ for every file I create with a text editor ?   Creating a file with a text editor like GNU Emacs, say myfile, another file called myfile~ is also created. Why is this superfluous file created ? Using cat on it displays nothing.  Thanks,


Right now there are two options a moderator can contact the team:   Pinging a team member in TL, or e-mail.   Both options are a bit crude, there's no easy way of knowing that a fellow mod has already contacted the team or an easy way to backtrack an issue. Certainly we do get things done, however our current tools and processes get in the way more often than not. What I would like would be a feature that:   Would allow me to send a message to the team, Instantly notify my fellow moderators about my message, Give us a rough idea of any progress (unread, pending, declined / completed / wtf?), All complete with a list of past messages.   I think the current feature that mostly resemble what I have in mind is mod messages, every time a moderator sends a mod message to a user, all moderators and the team are notified, and of course there's a handy list of past messages. The mod team bat signal would be more of an issue tracker than a private communication mechanism though, I don't expect the team to respond in any other way than a status. If there's need for discussion on an issue, well, we always have TL (sigh).  Thoughts?  TL;DR  I want an easy way of knowing that one of my fellow mods have communicated an issue to the SE team, and an equally easy way of knowing when and how the issue has been handled.    To address some of : This isn't a replacement for TL, or even worse a replacement for MSO/E or searching around before you ask. Some of the issues that the tool could be used for are:   So long, and thanks for all the fish1, I'll be taking a couple of weeks off, Could you please invalidate votes between these users, Could you please blacklist this IP, Eeek, that user posted their credit card number in their question, please purge2.   And should not be used for:   Anything that should be discussed in public,  Anything that's a search away,  Anything that would require a discussion.   One way we could limit the use of the tool would be to only allow specific categories of messages, and nothing else. You know, like a real issue tracker.  1 My ragequit message, don't anyone dare steal that ;)  2 True story. Sort of.    I must admit I like , it's unrealistic to expect SE to scale as well as the community does, and I'm all for shiny new toys. However:    - March 15, declined,  - March 17,    - Oct 30 '11, declined, Countless discussions for similar mod tools in TL, summarily dismissed.    So, at least three of my examples (more or less) have already been proposed as separate features, and declined (and I've only searched for 30 seconds). It appears that lobbying for those abilities to be made available to moderators doesn't seem to be an option, after all. Don't get me wrong, we get cool toys all the time, however there are always going to be actions that require SE's intervention.   My examples might not be the best examples, but that's irrelevant, the whole point of this feature request is that since we'll always need to communicate certain issues to the team, can we please do it in a way that's not absolutely braindead?

There are times when moderators come across things that only Stack Exchange employees can deal with. These include things like deleting sensitive information permanently from posts disassociating users from posts that require direct database access.  (The previous use case is now possible for moderators to do directly the moderator redaction tool)  Currently the workflow is:   See the post (either in normal site usage or via a flag) Go to chat Ping one of the community team (if they are around) Explain the problem   A far better workflow for the moderator would be to simply able to flag the post so it then appeared in an "employee only" queue somewhere. This could either be a page on the main Stack Exchange site or (better still) their inbox.  (OK I admit I hadn't fully thought this last bit out.)  This could either be a moderator "flag to devs" link on the post or a new option on the existing flag dialog (probably the better solution).  Now that moderators can't merge we have a fairly common situation where this would be very useful. A new users posts an answer (or question on sites that don't require registration) then loses their cookies and ends up creating another unregistered account (or two). Eventually the might even create a registered account. It used to be easy to merge the unregistered accounts into the registered ones, but now we either have to badger the OP to use the "merge accounts" form or ping the team somehow.  Having the "flag for team" option would be very useful in this scenario.


In my understanding a file, as I can see it in file explorer, is basically a hard link to the actual data. When I move this to another directory, the data is moved as well to that location. What happens with the actual data if I move a second hard link to a different directory? It is going to be saved in the location of which one of the two hard links?

I'd like to synchronise some configuration files via a file hoster like Dropbox. I could create a hard link in the software's configuration folder and let it point to my cloud storage directory.  When having done that, is there a difference between those two files? I read somewhere that both files are attributes of the file in the master file table and that there would be no difference at all.  On the other hand, on Windows, directory junctions via mklink can be found using dir /AL /S, so they somehow differ from real directories.  Is that correct?


I am writing a web service that has a lot of vicious competitors. Vicious as in: people have been getting DDoS'd within hours of setting up shop in this arena.  The service will consist of:   a website that you can sign up to and check on stats/etc... (all of which is served using https) a web service that runs in the port 8000+ range.   What (if any) port will be easiest to attack and/or bring down the server? The web server or the web service?  I know nginx has some pretty good DDoS protection so I am looking into that and load balancing for the website.  Any suggestions as to dynamic DDoS protection against various other ports with linux would be appreciated.

This is a  about DoS and DDoS mitigation.   I found a massive traffic spike on a website that I host today; I am getting thousands of connections a second and I see I'm using all 100Mbps of my available bandwidth.  Nobody can access my site because all the requests time out, and I can't even log into the server because SSH times out too!  This has happened a couple times before, and each time it's lasted a couple hours and gone away on its own.  Occasionally, my website has another distinct but related problem: my server's load average (which is usually around .25) rockets up to 20 or more and nobody can access my site just the same as the other case.  It also goes away after a few hours.  Restarting my server doesn't help; what can I do to make my site accessible again, and what is happening?  Relatedly, I found once that for a day or two, every time I started my service, it got a connection from a particular IP address and then crashed.  As soon as I started it up again, this happened again and it crashed again.  How is that similar, and what can I do about it?


I have a video file in my USB drive. I am going to give it to many people. I do not want anyone of them to copy the content. I am searching a way to make the file  I searched in Google. I came to know it is impossible to do.   So I don't want to make it impossible to copy. I just want to make it difficult. It should not be simple right click and copy OR drag and drop.   Is there any method to do that ? (I assume the user is using Windows.)

I am trying to make folder that everyone can view and can't copy,modify.    For all answers.I thinking about specially ms office files. I tried following methods  Software  - copy protect    - anti copy    This method can't protect save as and upload  MS office macro    Users can enable,disable macros.  MS office restriction    This is best choice but can't protect from file uploading.   Almost I found the solution. Way is combination of MS office restriction and restrict access from browsers using firewall or antivirus. But I don't exact how to do this.


This is a feature-request to support easily uploading retina-resolution (i.e. double resolution) images and automatically showing them at half-size.  It is currently possible to do this, but it takes a lot of tedious manual work.  Instead of using MarkDown, it's possible to use the <img> which allows resizing.  The following line  <img src="http://i.stack.imgur.com/De4De.png" width="374">   will produce this:    While the image is 2*374 = 744 pixels wide, it's resized to 374 pixels on a standard screen and it's shown in high resolution on a retina screen.  I use this method often in my posts.  This is a feature request to automate this procedure.  For example, the image upload dialog could have a checkbox to indicate that an image should be inserted at half size:    On  we have many users who use computers with retina screens and .  Some people are having difficulties with images being inserted at double size, others would simply like to be able to use high resolution images with relative ease.    If there are any existing non-official solutions, e.g. a userscript that automates this, please let me know!

On a modern Apple device with a high-resolution screen, if I take a screenshot of a window, this is what I get:    As you can see, when the image is displayed normally, it's too big.  Because my screen has two pixels per "point" (a @2x ratio), the  for me to display these is to use  <img src="[url]" width="[half of image width]">   Which produces this:    On my retina display, this is rendered at native resolution; on a non-retina display, it's appropriately downscaled so that it remains the correct size. Unfortunately, it requires manually checking the image width, dividing by 2, and typing in the HTML.  Can the image uploader do the hard work for us?   Nowadays, GitHub automatically enters the image width when dragging an image file to a comment field. They achieve it by reading the  from the PNG file, and appropriately interpreting that physical resolution.  Using  and  this is relatively simple to do. It would be great for Stack Exchange sites to do the same! (I imagine you can do this for pasted screenshots, too, although GitHub doesn't.)


Im just wondering which is better to use for security.   Can this be written in php? Id like to switch some of the functions of my site to javascript.  var withdrawing; function withdraw() {   withdrawing=false;   $.msgBox({     title:"Withdraw Funds",     content:"

Enter valid <?php echo $settings['currency_sign']; ?> address:
<input id=\"w_valid_ltc\" type='text' class='l' style='width: 100%;'>

Enter amount to be paid-out:
<input id=\"w_amount\" type='text' class='l' style='width: 100px; text-align: center;'>

Min. value: 0.001 <?php echo $settings['currency_sign']; ?>
We charge a fee 0.0002 <?php echo $settings['currency_sign']; ?> for each withdrawal.
",     type:"info",     opacity:0.8,     buttons: [{ value: "Withdraw" }, { value: "Cancel" }],     success: function(button) {       if (button=="Withdraw" && withdrawing==false) {         w_amount=$("input#w_amount").val();         w_valid=$("input#w_valid_ltc").val();         if (w_amount!='' && w_valid!='') {           $("#_withdraw_content").html('

&nbsp;&nbsp;&nbsp;');           withdrawing=true;           _requestWithdraw(w_amount,w_valid);         }         else {           alert('One of required fields stayed empty!');         }       }     }   });         return false; }

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


if (c.getQuery().contains("update") || c.getQuery().contains("delete") || c.getQuery().contains("truncate")             || c.getQuery().contains("drop")) {         throw new MensagemException(Mensagens.getMensagem("Only select is allowed"));   I have this simple code, that checks the string query. But it only checks lower case, what can I do to make it also verify any upper case without writing this over and over?

Say I have two strings,  String s1 = "AbBaCca"; String s2 = "bac";   I want to perform a check returning that s2 is contained within s1. I can do this with:  return s1.contains(s2);   I am pretty sure that contains() is case sensitive, however I can't determine this for sure from reading the documentation. If it is then I suppose my best method would be something like:  return s1.toLowerCase().contains(s2.toLowerCase());   All this aside, is there another (possibly better) way to accomplish this without caring about case-sensitivity?


I am new to blender and I am doing a school project with it and run into some issues. How do I fix this? I have heard about a material mode but I don't know how to enable that

I used sculpting on a plane, and things looks great. However, when I press P to play, the whole ground become a mess. I can see through it in various places, and there are also nasty looking black edges everywhere.  another problem, I made a UV Sphere to display the sky, but when I press , P to play it disappears!


I'm making a slideshow with LaTeX beamer class like this :  \documentclass[xcolor=dvipsnames]{beamer} \usepackage[french]{babel} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc}  \usepackage{listings} \usepackage{listingsutf8}  \begin{document}  \begin{frame}[fragile] \frametitle{Découpage et assemblage de lignes} \begin{lstlisting}[language=bash] some code \end{lstlisting} \end{frame}  \begin{frame}[fragile] \frametitle{Autres opérations} \begin{lstlisting}[language=bash] some code \end{lstlisting} \end{frame}  \end{document}   For convenient reasons, I would like the code of each frame to be inside a command created with \newcommand like this :   \documentclass[xcolor=dvipsnames]{beamer} \usepackage[french]{babel} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage{listings} \usepackage{listingsutf8}  \newcommand{\framei}{% \begin{frame}[fragile] \frametitle{Decoupage et assemblage de lignes} \begin{lstlisting}[language=bash] some code \end{lstlisting} \end{frame}}  \newcommand{\frameii}{% \begin{frame}[fragile] \frametitle{Autres operations} \begin{lstlisting}[language=bash] some code \end{lstlisting} \end{frame}}  \begin{document}  \framei  \frameii  \end{document}   But when I try to build my slideshow with these modifications, pdftex fail with a  Runaway argument? error.  Is there something wrong with my sources? or is it a LaTeX/beamer bug ?

This code fails with Emergency stop:  \documentclass{scrbook} \usepackage{listings} \newcommand{\demo}{% \begin{lstlisting} foobar \end{lstlisting} }  \begin{document} \demo \end{document}   Why?


Let $\mathbb R \supseteq D := (-\infty,-1) \cup \{0\} \cup (1, +\infty)$. We define a function $f: D \to \mathbb R$ by $$f(x) = \begin{cases} x+1 &\text{if} \quad x \in (-\infty,-1) \\ x-1 &\text{if} \quad x \in (1, +\infty) \\ 0 &\text{if} \quad  x =0 \end{cases}$$  I would like to prove that $f$ is continuous on $D$. Clearly, $f$ is continuous on $D - \{0\}$, so it suffices to prove that $f$ is continuous at $0$.  Clearly, $f(0) = 0$. Let $U$ be an arbitrary neighborhood of $0$ in $\mathbb R$. Let $U'= (-1,1) \cap D =$ $\{0\}$. Then $U'$ is a neighborhood of $0$ in $D$. We have $f[U'] = \{0\} \subseteq U$. As such, $f$ is continuous at $x=0$.    My questions:   Because $0$ is not a limit point of $D$, $\lim_{x \to 0} f(x)$ is not defined. As such, I can not appeal to the notion limit of a function at point $x=0$. Hence I must use the more general definition of continuity in the metric space. Is my understanding correct? Could you please verify if my proof looks fine or contains logical gaps/errors? Any suggestion is greatly appreciated.   Thank you so much!

For example if my function is $f:\{1\}\longrightarrow \mathbb{R}$ such that $f(1)=1$.  I have the next context:  1) According to the definition given in Spivak's book and also in wikipedia, since $\lim_{x\to1}f$ doesn't exist because $1$ is not an accumulation point, then the function is not continuous at $1$ (Otherwise it should be $\lim_{x\to 1}f=f(1)$).   2) According to  , as far as I can understand a function is continuous at an isolated point.  I don't understand.   Edit:   Spivak's definition of limit: The function $f$ approaches to $l$ near $a$ means $\forall \epsilon > 0 \; \exists \delta > 0 \; \forall x \; [0<|x-a|<\delta\implies |f(x)-l|<\epsilon]$ Spivak's definition of continuity: The function $f$ is continuous at $a$ if $\lim_{x\to a}f(x)=f(a)$


I want to increase the ulimits and used the commands for it   ulimit -n 1024 ulimit -n 10000 bash: ulimit: open files: cannot modify limit: Operation not permitted   After lot of searching. I got a my links but By taking the reference of  link I just follow each and every command in the terminal but can't increase the ulimit in the system why and How will I do it Can anybody please explain this.

This is happening on Ubuntu Release 12.04 (precise) 64-bit Kernel Linux 3.2.0-25-virtual  I'm trying to increase the number of open files allowed for a user. This is for my eclipse java application where the current limit of 1024 is not enough.  According to the posts I've found so far, I should be able to put lines into   /etc/security/limits.conf like this:  soft nofile 4096 hard nofile 4096   to increase the number of open files allowed for all users.  But that's not working for me and I think the problem is not related to that file.  For all users, the default limit is 1024, regardless of what is in /etc/security/limits.conf (I rebooted after changing that file)  $ ulimit -n 1024   Now, despite the entries in /etc/security/limits.conf I can't increase that:  $ ulimit -n 2048   -bash: ulimit: open files: cannot modify limit: Operation not permitted The weird part is that I can change the limit downwards, but can't change it upwards - even to go back to a number which is below the original limit:  $ ulimit -n 800 $ ulimit -n 800  $ ulimit -n 900  -bash: ulimit: open files: cannot modify limit: Operation not permitted   As root, I can change that limit to whatever I want, up or down. It doesn't even seem to care about the supposedly system-wide limit in /proc/sys/fs/file-max  # cat /proc/sys/fs/file-max 188897  # ulimit -n 188898 # ulimit -n  188898   But even I get eclipse to run as root, my application still crashes because of "Too Many Open File" exception!   So far, I haven't found any way to increase the open files limit for a non-root user.  How should I properly do this? I have looked at several other posts but no luck!


Is it possible to use Windows touchpad driver in Ubuntu? I have a Dell n5110 and the touchpad is not recognized. I cannot use scroll, and most annoying, while typing the pointer usually jumps if the touchpad is touched. I see that there are lots of questions here and on the internet about this issue. Some claim to work, but I tried everything with no results.

I have Dell Laptop " N 5110 "    How do make 2 finger scrolling work + 2 fingers zoom in & zoom out work How to Fn + f3 To lock touchpad How to configure 1 2 3 as shown in pic   3.1 For Ubuntu Software Center  3.2 For System Settings  3.3 For Screen Off      Nothing Work & i did google but find nothing   xinput list ⎡ Virtual core pointer                             id=2 [master pointer  (3)] ⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)] ⎜   ↳ PS/2 Generic Mouse                        id=13   [slave  pointer  (2)] ⎣ Virtual core keyboard                          id=3   [master keyboard (2)]     ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]     ↳ Power Button                              id=6    [slave  keyboard (3)]     ↳ Video Bus                                 id=7    [slave  keyboard (3)]     ↳ Video Bus                                 id=8    [slave  keyboard (3)]     ↳ Power Button                              id=9    [slave  keyboard (3)]     ↳ Sleep Button                              id=10   [slave  keyboard (3)]     ↳ Laptop_Integrated_Webcam_HD               id=11   [slave  keyboard (3)]     ↳ AT Translated Set 2 keyboard              id=12   [slave  keyboard (3)]     ↳ Dell WMI hotkeys                          id=14   [slave  keyboard (3)]


How do we know the logic we use to logically infer is correct? What makes it correct? Why is  "If X exists, then Y exists. X exists. Therefore Y exists." true?

I would like to hear some philosophical arguments which justify the use of logic.   Additionally, if a justification of logic takes the form of an inference, is it a problem if this inference itself makes use of logic.   Can we justify logic in a way that is not circular? Is a circular justification a bad thing?  Thanks.


we're hoping somebody out there can help us with a new Cubot S208 smart phone we've just bought. We've been using it for a couple of weeks on various wi-fi networks and not experienced any problems until 2 days ago. We tried to connect to our home network which we'd connected to many times over the last 2 weeks but we got the Obtaining IP address message. This stays on the screen for ages, then the message says Avoided Bad Internet Connection. I tried out the phone on a neighbours wi-fi network (which has the same security type WPA-PSK with its own password), and this worked okay. We used it last night and it intermittently logged onto 1 or 2 different wi-fi networks in town, other networks we got the same error message as we're now getting at home Avoided Bad Internet Connection. So, here's what we've tried so far:   Took the handset back to factory settings Tried connecting to our home wi-fi on its own (we switched off our wireless laptop in case it was causing the problem) We deleted our home wi-fi connection and re-entered it on the handset   And today we're still getting the same error message when trying to connect at home. Our wireless router BTW is a Belking54g (not sure if that's the problem?). Does anybody have any suggestions what we can do to rectify this problem as currently we're not able to use the handset at home for internet now. One other thing; we don't have a SIM card in the handset yet (in the process of buying one).  We've seen lots of other comments online where other devices are getting exact same problem, and we've also seen some software online that suggets it can cure it but would appreciate some honest advice.  Really hope somebody out there can help us. Thanks for listening :-)

The connection to my work wifi just failed and below the network my phone is saying "Avoided poor Internet connection". What does this mean exactly? Has the phone detected that it can't get out to the wider Internet or did the network fail to allocate an IP address or something else?  Not sure if it matters but this is on a Galaxy Nexus.


Book about a traveling salesman that discovers a buried UFO, he gets home and finds a portal in his front door. He meets some aliens and exchanges a gravitational vehicle for paint. In both exchanges it was not the object what was exchanged but the concepts. Excellent book indeed.

A man's house gets altered by some rat-like creatures, so it is somewhat bent in on itself.  It has become a portal to another part of the universe.  He pokes around on the "other side" because he is after his dog that wandered off.  He meets up with some aliens (seemingly friendly) moving around on some anti-gravity saddles.  He tries to barter with them! Very weird and original story!  Anyone know what this is?


The following command is executed at system startup and the PHP script is running in the background continuously with a loop:  screen -dmS some-friendly-name php /path/to/file.php   Unfortunately, I accidentally deleted /path/to/file.php file. But when I reattach to the screen session, I can see the script is still running (giving output).  Is there a way to recover this file, other than the standard file recovery processes? Could it be stored in a PHP buffer etc?

Suppose an apache log file gets deleted but it's held open by apache; then this is what I am doing:  pid=$(lsof | grep text.txt | awk '/deleted/ {print $2}') fd=$(lsof | grep text.txt | awk '/deleted/ {print $4}' | grep -oE "[[:digit:]]{1,}")  cp /proc/$pid/fd/$fd directorytobecopied/testfile.txt   This is what I am doing to recover the file and put it back where it was. Is there any simpler way of doing this because above code doesn't look good. Furthermore how do I know from where the file was deleted(directorytobecopied) so that I don't have to manually ask somebody where the file was located originialy and put it back there.


can one get resurrected with a single Horcrux multiple times, or can the Horcrux only be used once? for example, back when Voldemort was alive and had 7x Horcruxes, would killing Voldemort's body be about as good as taking out 1 of the Horcruxes?

I think I misunderstand Horcruxes here - are they used up? Or do they just exist to stop the person dying but are not actually 'used up' in the process? By this logic someone could be killed infinite times and still not die?


Our son is about 3 months old. As he's starting to become a little more alert, I notice that his right eye isn't always tracking with his left. Obviously he will have to see an optometrist eventually for a check up somewhere down the road. At the moment though, since he's so young, is this something we should be concerned about?

My youngest (14 months) has started showing signs of either strabismus or ambylopia (both commonly referred to as "lazy eye", where one eye seems to track differently than the other when the child is tired or isn't focusing).  We're going to see an ophthalmologist once the pediatrician weighs in and recommends one, and I'm interested in suggestions for what I should look for in an ophthalmologist, and in what we should do to prepare for the visit.  Particularly, how important is it that we find one that specifically mentions these conditions as things they specialize in?  They're fairly common conditions (affecting over 4% of children), so I would expect most pediatric ophthalmologists to have as one of their main purposes helping to diagnose and treat lazy eyes; but many do not mention them in their list of specializations.    And, in terms of preparation, do we need to keep track of time or length of lazy eye bouts?  Should we take any videos?  Our pediatrician hasn't noticed this in her periodic checks, but I suspect that he's more focused during these visits (a person he's not that used to, who is talking a lot to him).  I worry the ophthalmologist will have the same problem - not be able to diagnose because of lack of presentation during the visit.


In Counter-Strike: Global Offensive, you can collect guns. These guns can replace the default in-game guns. They do not change gameplay at all, and are purely cosmetic.  How can I get new guns?

Just curious as to how to obtain item drops from the last update.  To clarify, item drops as in weapon skins, crates, anything else Valve added without letting us know, etc.  It seems that after playing a bit, I've gotten no drops, but I've seen players who've gotten drops after a few short minutes of gameplay, but I've been playing for hours.  Is the item drop system like TF2, where you can just idle, get an item drop, come back? Is it like Dota2, where you have to be in the matchmaking system and complete matches for the chance to get drops? Or do you have to be MvP to get item drops? Is it a certain time you play the game?   Also, are weapon and crate drops independent or dependent on each other? Meaning, is the drop counter shared between Weapons and Crates, or are they both separate drop counters?


In Linux, what does the d mean in the first position of drwxr-xr-x?  And what are all of the possible letters that could be there, and what do they mean?  I'm trying to learn more about the Linux file permissions system, and I'd like to see a list of the character meanings for the first slot.

I've never really got how chmod worked up until today. I followed a tutorial that explained a big deal to me.   For example, I've read that you've got three different permission groups:   owner (u) group (g) everyone (o)   Based on these three groups, I now know that:   If the file is owned by the user, the user permissions determine the access. If the group of the file is the same as the user's group, the group permission determine the access. If the user is not the file owner, and is not in the group, then the other permission is used.   I've also learned that you've got the following permissions:   read (r) write (w) execute (x)   I created a directory to test my newly acquired knowledge:  mkdir test   Then I did some tests:  chmod u+rwx test/ # drwx------ chmod g+rx test/ # drwxr-x--- chmod u-x test/ # drw-r-x---   After fooling around for some time I think I finally got the hang of chmod and the way you set permission using this command.    But...  I still have a few questions:   What does the d at the start stand for? What's the name and use of the containing slot and what other values can it hold? How can I set and unset it? What is the value for this d? (As you only have 7=4+2+1 7=4+2+1 7=4+2+1) Why do people sometimes use 0777 instead of 777 to set their permissions?   But as I shouldn't be asking multiple questions, I'll try to ask it in one question.  In UNIX based system such as all Linux distributions, concerning the permissions, what does the first part (d) stand for and what's the use for this part of the permissions?


What if I fill liquid nitrogen in tube of two wheeler?? Is it OK?

I am completely new to riding bikes and know that are usually filled with air but nowadays some people fill them with Nitrogen instead.  I don't know why they prefer to fill their tires with nitrogen as it is more costly than filling them with air.  What are the benefits of filling tires with Nitrogen?


I have a datasets where all the dates have the following format:  2012-10-09T19:00:55Z   I'd like to be able to be able to use methods like .weekday on them. How do I convert them to the proper format in Python?

I need to parse  strings like "2008-09-03T20:56:35.450686Z" into Python's datetime type.  I have found  in the Python standard library, but it is not very convenient.  What is the best way to do this?


Kindly help me understand the difference between conduction current and displacement current. Quick searches explain that displacement current is associated with changing electric field, frankly speaking, it is too technical for me to understand.   Also, please relate it to why Capacitor allows AC and blocks DC. They say time varying voltage(AC) produces displacement current which can flow through the insulator while fixed voltage(DC) produces conduction current which cannot flow through the insulator. This is what made me put this question to you.  Thanks in advance.

I am confused with this! How does a capacitor block DC?   I have seen many circuits using capacitors powered by a DC supply. So, if capacitor blocks DC, why should it be used in such circuits? Also, the voltage rating is mentioned as a DC value on the capacitor. What does it signify?


Mathematica gives: $$S= -\frac{1}{12}\pi^2\log(2)+\frac{\log(2)^3}{6}+ \frac{7}{8}\zeta(3)$$  How can I prove it?

From the functional equation   $$\text{Li}_{3}(z) + \text{Li}_{3}(1-z)+ \text{Li}_{3} \Big( 1 - \frac{1}{z} \Big) = \zeta(3) + \frac{\ln^{3} (z)}{6}+ \frac{\pi^{2} \ln (z) }{6}- \frac{\ln^{2} (z) \ln(1-z)}{2}$$  one can determine the value of $\text{Li}_{3} (\frac{1}{2} )$ since   $$ \text{Li}_{3}(-1) = \sum_{n=1}^{\infty} \frac{(-1)^{n}}{n^{3}} = -\Big(1 - 2^{-2} \Big) \zeta(3) = - \frac{3}{4} \zeta(3) $$  But how does one derive that functional equation?   A similar functional equation for the dilogarithm can be derived using the integral representation $$ \text{Li}_{2}(z) = - \int_{0}^{z} \frac{\ln(1-t)}{t} \ dt $$  Is there a better way to find the value of $\text{Li}_{3} (\frac{1}{2} )$?


There was a time not long ago when this question would (and should!) of been marked as a duplicate of  or many others...  But the landscape of Ubuntu has changed since 12.04, and it will again with 14.04.  My question is this:  Who should run the LTS now? Is it just business and servers, or is it now casual users, home users and students as well?  On the other hand, since the regular releases are not as major as they used to be, would they be safe for students and casual users? Could a someone depend on their laptop day in and day out on a regular release?  What are the Pros and Cons of each now?  Specifically I ask because I'm an engineering and physics student. I do a lot of programming, CAD (VMWared SolidWorks), and writing (LaTeX). I want to know whats best for me since I can't have my computer unstable.

What are the differences between an Ubuntu Long Term Support release (LTS) and a normal release?


My Excel table is really wide and long, how can I make it to fit my page and go through on lower pages (not stay on the same page)? I have used the longtable package but it doesnt work with resize box. I used the \tiny command but my table still does not fit on the page. How can I fix that?

I have a table that I want to insert on a page, but at least one (perhaps both) of the following conditions are met:   The table is too wide to fit within the text block or page. That is, I'm exceeding some horizontal restriction. The table is too tall to fit within the text block or page. That is, I'm exceeding some vertical restriction.   What are my options to make this table fit? If it doesn't fit, regardless of my attempts, what other options exist?


I have a simple code:   delx=0.1; delt = 10**-3; r = delt/delx**2   I get r = 0.09999999999999998 in console. Why are there round-off errors for such a small number of decimal points? How do I correct this?

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


What's the difference of light between taking photos near sunset or during midday sunshine if there is any? Why would you go for a photo at sunset instead of a daylight photo when the sun is higher in the sky and vice versa?

I usually get better light at sunrise (compared to sunset). I do though hate to wake up early in the morning to use that light ;)  What are the biggest differences between sunrise and sunset?


I have edited my profile at Stack Overflow many times. The edit form always reports as successful,  but my name at Stack Overflow is still  despite all my tries.

How can I change (or remove / reset ) my name on a site in Stack Exchange network?


I am looking for an example of an associative noncommutative ring $R$ with the following property: for $r,s \in R$, $$ rs \neq 0, \text{  but  } sr = 0. $$ Moreover, do rings for which this cannot happen have a name?

Prove that in general the set of the right zero divisors is different from the set of left zero divisors in ring $R$.   The ring is arbitrary. Does exist general proof for it ?  Attention that the problem is comparing two sets. Thank you.


Given vectors  $v_{1}, v_{2},\dots,v_{k}$ and $w_{1}, w_{2},\dots, w_{k}$ which satisfy condition $\forall i, j \in \{1,\dots,k\}$, $v_{i}\cdot v_{j} = w_{i}\cdot w_{j}$ (dot product), prove that there exist such unitary transformation $U$ such that that $U(v_{i})=w_{i}$.  I can pretty much see what's going on here. These two sets of vectors are just rotated, so this tells me that there must be some kind of isometry that rotates them, but this is just intuition.

Suppose I have two sets of vectors, $E_1=\{v_i\}_{i=1}^{k}$ and $E_2=\{u_i\}_{i=1}^{k}$, with each vector belonging to $\mathbb{C}^k$.  When is it possible to find a unitary matrix that maps $E_1$ to $E_2$? Is enough for the pairwise inner products between vectors in the set to be equal?


What is the meaning of the crawling ritual in Breaking Bad season 3 episode 1. It takes place right at the beginning of episode 1. Several farmers in a Mexican village are crawling towards some kind of shrine, decorated with flowers. The twin killers arrive in the Mercedes and join the crawling.  Presumably this is a religious ritual, but what is their religion?

At the start of Season 3 Breaking Bad, we see a bunch of villagers and Tuco's cousins crawling on their bellies towards some shrine where they put a drawing of Walter White as some kind of "offering".  Why were the villagers and the cousins crawling towards this shrine?


I recently deleted Windows from my Laptop and installed Ubuntu to use it as a main operating system (no other operating system beside Ubuntu installed). So I want to delete Ubuntu now. I want no operating system on my Laptop. How can I do it?

By just typing some commands, how can Ubuntu be uninstalled? I don't want to install Windows or anything, leaving my PC without an OS.  Would this command work?  sudo rm -rf /


Let $I=]0,\infty[$ equipped with the metric $d(x,y)=\lvert\ln(x)-\ln(y)\rvert$, $\forall x,y \in I$. Prove that $(I,d)$ is complete. Any help, and thanks in advance.

Given the metric space $(X,d)$ with $X := (0,\infty)$ and $d:=|\ln(x)-\ln(y)|$, how can I show that $(X,d)$ is complete?  I need to prove that any Cauchy sequence converges, so:  If $(x_n)$ is a Cauchy sequence in X, then it follows for all $\epsilon \gt 0$ that there exists an $n_0 \in \mathbb{R} : \forall n,m \leq n_0: d(x_n,x_m) \lt \epsilon$.  I couldn't find a direct way to prove this, I guess an indirect approach might go as follows:  Let $(x_n)$ be a Cauchy sequence in X and assume that it does not converge, then it follows that there exists an $\epsilon > 0$ such that for an arbitrary $x \in X : \forall n \in \mathbb{N}: d(x_n - x) \geq \epsilon$ and this would contradict the fact that $(x_n)$ is a cauchy sequence. I'm assuming that this is incorrect since I didn't even use the given metric and this proof would mean that no cauchy sequence converges.  So how can I prove that this metric space is complete? And in general is there a way how to approach these completeness proofs?


I want to insert a record into the data-base, I don't know where's the probolem  this is my code !    <?php  if ($_SERVER['REQUEST_METHOD'] === 'POST') {     $status = "";     $name = $_POST['name'];     $username = $_POST['username'];     $email = $_POST['email'];     $password = $_POST[$password];      $query = "INSERT INTO admins (name, email, username, password) ";      $query .= "VALUES ('{$name}','{$email}','{$username}','{$password}')";      $result = mysqli_query($connect , $query);      if (isset($result)){         $status = "Admin has been added";     }else {         $status = "Admin hasn't been added ";     } } ?>  <form action="add_user.php" method="post">
Name
     <input name="name" placeholder="Name">
Username
     <input name="username" placeholder="Username">
E-mail
     <input name="email" placeholder="E-mail">
Password
     <input name="password" placeholder="Password" id="password" type="password">
Confirm Password
     <input name="confirm_pass" placeholder="Confirm Password" id="confirm_password" type="password" onkeydown="ValidatePass()">

         <input type="submit" value="Create User dis" disabled>

<?php ?>
 </form>     I know that there night be sqlInjections !  don't worry about that that's only for local development and learning purposes:D    please Help !

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


How to I make the answer display in two decimal places?  runningCalories  = 0.0175 * RUNNING_METS * weight * TIME_RUNNING; System.out.println(name + " burned an estimated " + runningCalories + " calories running.");

What I would like is a method to convert a double to a string which rounds using the half-up method - i.e. if the decimal to be rounded is 5, it always rounds up to the next number. This is the standard method of rounding most people expect in most situations.  I also would like only significant digits to be displayed - i.e. there should not be any trailing zeroes.  I know one method of doing this is to use the String.format method:  String.format("%.5g%n", 0.912385);   returns:  0.91239   which is great, however it always displays numbers with 5 decimal places even if they are not significant:   String.format("%.5g%n", 0.912300);   returns:  0.91230   Another method is to use the DecimalFormatter:  DecimalFormat df = new DecimalFormat("#.#####"); df.format(0.912385);   returns:  0.91238   However as you can see this uses half-even rounding. That is it will round down if the previous digit is even. What I'd like is this:  0.912385 -> 0.91239 0.912300 -> 0.9123   What is the best way to achieve this in Java?


I have two laptops, and one is working fine with windows 7. Thew other just  died, and I decided to try Linux on that. The computer is working, and I can access the boot menu, but it wont start windows anymore. How can I install Linux on that computer? I have no files or apps that I need to keep on that laptop.  Thank you

I would like to see a full how-to guide on how to install Ubuntu.


So I feel like this is either a dumb question or a dupe, but here we go... If I go to the "Users" page on a site and search, and then sort by all-time reputation (as ), I get very confusing results:  I don't understand how these are sorted. There is one person with over 1K rep, and they are not (in any way that I can see) placed above the person with 1 or 19.  How are these sorted?

When filling in the "Type to Find Users" , it seems to sort by exact match and then by reputation when I am on the reputation tab.   For example, please consider the following search results:    This threw me off since I thought that the sort order is reputation. I guess this often might give people what they want, but when picking a popular name is shows a lot of 0 rep users. Maybe adding a filter for low rep to the exact match might give more expected results, or just sorting on Rep?


In Avengers Endgame we see that Natasha and Hawkeye were tasked to get the soul stone. After events of Avengers Infinity War, especially after events on Titan, everyone knows that soul stone needs sacrifice if it were to be taken from Vormir.    So the question is when Natasha and Hawkeye were sent for it, did they already know about sacrifice thing? If they knew, why they fought for sacrificing themselves in vormir and not planned who will die earlier?

So there are two teams in Avengers: Endgame: Natasha (Black Widow) and Clint (Hawkeye)/Nebula and War Machine.   Yet Black Widow and Hawkeye were chosen for the mission to Vormir. So did Nebula know to send them since one loved one had to be sacrificed and she gathered that they both share a history or was it just a normal team separation?


public class SumReducer extends Reducer<Text, Text, Text, Text> {      Map<String, List<String>> map = new HashMap<String, List<String>>();     List<String> l1=new ArrayList<String>();      List<String> l2=new ArrayList<String>();     List<String> l3=new ArrayList<String>();     List<String> l4=new ArrayList<String>();     @Override     public void reduce(Text key, Iterable<Text> values, Context context)     throws IOException, InterruptedException     {                 int j=0;        String[] wordCount = new String[100];       List<String> Final = new ArrayList<String>();       String mapop = "";         for (Text value : values) {              wordCount[j] =value.toString();             j++;         }         for(int i=0;i<j;i++){             //Final= Final+","+wordCount[i];             Final.add(wordCount[i]);          }          String key1=key.toString();         map.put(key1, Final);           l1.add("1");         l2=(map.get("1"));         int total_nodes=l2.size();          for(int i=0;i<total_nodes;i++)         {                 if(l2.size()!=1)           {              l1.add(l2.get(0));              **l3=map.get(l2.get(0));**              **int cs=l3.size()**;//---------------NULLPOINTER EXCEPTION ON THIS LINE              for(int e=1;e<l2.size();e++)             {                  for(int k=0;k<cs;k++)                 {                     String keymap=l2.get(e);                     if(keymap==l3.get(k)){                         l4.add(keymap);                        //System.out.println(l4);                         break;                     }                  }             }    }   This code runs perfectly in java but throws  NULL pointer exception in mapreduce. Value of l3(list) is not getting initialized at all. I am trying to implement bruteforce algorithm for finding cliques. The program has static inputs with 5 nodes in a graph all connected to each other.  This is not the whole program but just a snippet of the code where the error is shown.

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?


I want to make my application single instance application. While launching a new instance i want to check for already running instance. My application is written in java.

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.


Is there an established way to assess the prevalence of data mining (as in specification search, not in the machine learning sense) in academic publications?  I vaguely remember hearing something about meta studies plotting p-values against sample-sizes or something of that sort, but I can't seem to find a single reference and fail to see right-away why this would be informative.

The phrase p-hacking (also: , "snooping" or "fishing") refers to various kinds of statistical malpractice in which results become artificially statistically significant. There are many ways to procure a "more significant" result, including but by no means limited to:   only analysing an "interesting" subset of the data, in which a pattern was found; failing to adjust properly for multiple testing, particularly post-hoc testing and failing to report tests carried out that were not significant; trying different tests of the same hypothesis, e.g. both a parametric and a non-parametric test (), but only reporting the most significant;   experimenting with inclusion/exclusion of data points, until the desired result is obtained. One opportunity comes when "data-cleaning outliers", but also when applying an ambiguous definition (e.g. in an econometric study of "developed countries", different definitions yield different sets of countries), or qualitative inclusion criteria (e.g. in a meta-analysis, it may be a finely balanced argument whether a particular study's methodology is sufficient robust to include); the previous example is related to optional stopping, i.e., analyzing a dataset and deciding on whether to collect more data or not depending on the data collected so far ("this is almost significant, let's measure three more students!") without accounting for this in the analysis; experimentation during model-fitting, particularly covariates to include, but also  regarding data transformations/functional form.   So we know p-hacking can be done. It is often listed as one of the  and was mentioned in the ASA report on statistical significance, , so we also know it's a Bad Thing. Although some dubious motivations and (particularly in the competition for academic publication) counterproductive incentives are obvious, I suspect it's hard to figure out quite why it's done, whether deliberate malpractice or simple ignorance. Someone reporting p-values from a stepwise regression (because they find stepwise procedures "produce good models", but aren't aware the purported p-values are invalidated) is in the latter camp, but the effect is still p-hacking under the last of my bullet points above.  There's certainly evidence that p-hacking is "out there", e.g.  looks for tell-tale signs of it infecting the scientific literature, but what is the current state of our evidence base about it? I'm aware that the approach taken by Head et al was not without controversy, so the current state of the literature, or general thinking in the academic community, would be interesting. For instance do we have any idea about:   Just how prevalent is it, and to what extent can we differentiate its occurrence from publication bias? (Is this distinction even meaningful?) Is the effect particularly acute at the $p \approx 0.05$ boundary? Are similar effects seen at $p \approx 0.01$, for instance, or do we see whole ranges of p-values affected? Do patterns in p-hacking vary between academic fields? Do we have any idea which of the mechanisms of p-hacking (some of which are listed in the bullet points above) are most common? Have some forms proven harder to detect than others because they are "better disguised"?   References  Head, M. L., Holman, L., Lanfear, R., Kahn, A. T., & Jennions, M. D. (2015). . PLoS Biol, 13(3), e1002106.


While compiling my document, I am getting the following error message. I updated my packages and especially, kvsetkeys and kvoptions packages. Kindly guide me how to fix this.  \documentclass[12pt,a4paper]{article} \usepackage{amsmath,amsthm,amssymb,thmtools} \usepackage{mathtools} \usepackage[width=1.00cm, height=1.00cm, left=3.00cm, right=3.00cm,  top=2.00cm, bottom=3.00cm]{geometry} \usepackage{xcolor} \usepackage{wasysym,textcomp,array,arcs,polynom,cancel,enumerate,dcolumn} \usepackage{sectsty} \usepackage[colorlinks,linkcolor=magenta,citecolor=capri]{hyperref} \usepackage[nameinlink]{cleveref} \hypersetup{ colorlinks=true, linkcolor = {teal}} \usepackage{ebgaramond} \chapterfont{\color{gray}} \sectionfont{\color{brown}} \subsectionfont{\color{blue}} \paragraphfont{\color{green!50!black}} \usepackage[most,listings]{tcolorbox} \usepackage[left]{showlabels} \usepackage{varwidth}  \begin{document}  bla bla bla  \end{document}     I am unable to fix this error.

Just updated to the 20 December build of the Oberdiek package, on my TeXLive installation. Files that compiled without problems are now throwing the following error:   ./Preamble.tex:78: Undefined control sequence. \kv@processor@default ...lt {#1}{\etex@unexpanded                                                    {#2}}}\KVS@temp    which appears when I use \declaretheoremstyle of the thmtools package. The packages kvdefinekeys and kvsetkeys are installed and working well.  Does anybody know an explanation and a workaround?  Here is a compilable example  \documentclass{amsart} \usepackage{thmtools}  \declaretheoremstyle{mythmstyle} \begin{document} \end{document}


Currently running Ubuntu 15.10 on azure and Installed vnc4server and gnome group packages but still screen showing gray out. configuration file is define below:  $cat .vnc/xstartup unset SESSION_MANAGER exec /etc/X11/xinit/xinitrc [ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup [ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources xsetroot -solid grey vncconfig -iconic & x-terminal-emulator -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" & x-window-manager &  gnome-panel & gnome-settings-daemon & metacity & nautilus -n & gnome-terminal &  $cat /etc/vncserver/vncservers.conf VNCSERVERS="1:adminuser" VNCSERVERARGS[1]="-geometry 1024x768"

Currently using ubuntu 15.10 on azure and installed the gnome and vnc4server latest version on ubuntu. Please find log file below:  Current VNC client screen:    $ cat .vnc/myhost1\:1.log    --cut-- VNCSConnST:  Server default pixel format depth 16 (16bpp) little-endian rgb565 VNCSConnST:  Client pixel format depth 8 (8bpp) colour-map Window manager warning: Invalid WM_TRANSIENT_FOR window 0x20000c specified for    0x20000b (I        nitialization error). Error org.freedesktop.DBus.Error.NameHasNoOwner: Could not get owner of name    'org.gnome.ze        itgeist.Engine': no such name amdxdg-su: no graphical method available for invoking '/usr/bin/amdcccle' as 'root'  $ cat .vnc/xstartup unset SESSION_MANAGER  [ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup [ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources  vncconfig -iconic &  gnome-panel & gnome-settings-daemon & metacity & nautilus -n & gnome-terminal &   How to get 24bit color with wide screen (Now I getting square screen in vnc client)


I stay logged into Google. I would very much like to permanently blacklist sites that I know to be spammy or low quality from showing up in some of the modules like news and search. Any suggestions on how? I know how to do it case by case in search (-site:lame.example.com) but that's not permanent.  EDIT: The solution presented below (Personal Blocklist) does in fact work for search (thanks!) but not for news - anyone?

Is it possible to configure Google somehow to permanently ban search results from domains that I know 100% are never, ever going to make me happy?  Something cookie/session based maybe?  E.g. I want to ban (permanently, forever and always) results from experts-exchange.com.  Every time I click results that take me to their page I just want to scream.    Update!  Google has released a Chrome Extension to allow users to block individual site from Google search results!  .  (Since this question has been closed, I cannot answer it.)


How to evaluate those infinite series? How are they called?  $$ \sum_{k=1}^\infty \frac{k}{2^k} \quad \text{and} \quad \sum_{k=1}^\infty \frac{k^2}{2^k} $$  I'm really sorry for asking, but I can't figure out how to google such stuff when I even don't know the names/categories.

How can I evaluate $$\sum_{n=1}^\infty\frac{2n}{3^{n+1}}$$? I know the answer thanks to , but I'm more concerned with how I can derive that answer. It cites tests to prove that it is convergent, but my class has never learned these before. So I feel that there must be a simpler method.  In general, how can I evaluate $$\sum_{n=0}^\infty (n+1)x^n?$$


I recently came across this piece of spam:    Now, it's spam, and it's been deleted, but a lot of times, we get questions that are just plain off topic by legitimate users, and not suitable for any other sites in the Stack Exchange network.  We wouldn't delete these, we'd just put them on hold as "Off Topic".  Given that we are rolling all of the old close reasons into "off topic", for a case like this, I generally have to do the following:   Click "Off Topic" Select "Custom" Type at least 15 characters "This post is not suitable on any site in the Stack Exchange network".   That said, when I click the first "Off Topic" radio button, I'd like to not have to select any other reason to close the post.  I should be able to click close and have the system auto-insert some standardized text (which can be standardized per-site, or for the entire network) saying "you shall not pass/do not pass go, do not collect $200".  The workflow of having to select two items and possibly type custom text is excessive for things that should be one-click operations.  Basically, there are times where obvious is obvious, and we shouldn't have to go through extreme hand holding/extra work in order to express that.  Just don't make it more painful for me to stamp it as off topic when it's so blatantly obvious.

I know that useability and friendliness are given priority in the features implemented on StackExchange, but after using the new close-as-off-topic flow for the first time I would have to say I'm somewhat underwhelmed.  Why do we not have a simple It's off topic type reason? And why do I have to write half a book chapter as my custom close reason, especially when I can go back and edit the automatically posted comment so that it's way shorter?   This question complaint is prompted by  here on Meta. It's off topic, plain and simple. We now have a bunch of people wanting to close it, all potentially writing their own custom close reasons, it's just messy suboptimal. Regardless of how nice and friendly you want to be to the user, this particular question shouldn't need an explanation.    Does the off topic flow have to stay this way? Can we allow higher rep users to close as off topic without having to specify a (really long) custom reason, maybe have some canned reasons like we used to?  Edit: just to be clear, there are still three canned close reasons, but none of them were applicable to this example. The second one is closest, but does not appear to seek input... is quite different to It's a question, but doesn't belong here in any way, shape, or form.