undelete big files - mission impossible?

I've accidentaly deleted outlook.pst (6.7GB) file, while there was only 400MB free space left on primary NTFS partition (winxp).  I've tried several recovery tools to get this file back. "Ontrack Easy Recovery Pro" found 0 pst files (complete scan mode), while "Recover My Files" in sector scan mode found 5 pst's, but 4 of them of sizes from 3 to 28 KB, while the 5th one - 1Gb.  I've managed to succesfuly recover 1Gb pst file, which was 1 year old copy (the one used after the latest windows reinstall).  Now, I'm frustrated and confused   Why 1 year old file was succesfuly recovered if there were only 400MB left on primary partition? Where's 6.7GB file gone? I did some reading (), and it seems that there's almost no probability to retrieve the file I'm looking for, but wait - none of recovery tools i've used found zero-sized pst file, moreover - if due to fragmentation a file might be corrupted - we could use scanpst.exe to fix some errors and survive with 10 or 100 emails missing - whatever. Could you please recommend some more sophisticated recovery tools for this particular task?   Appretiate your help - thanks in advance


How was the Resistance able to run out of fuel?

In Star Wars: The Last Jedi     It's a major plot point that the Resistance must find some way to escape the First Order before their ships run out of fuel.    In space, there is very little resistance to motion, so once something starts moving, it tends to stay moving. This is why real life spacecraft barely need to burn fuel once in orbit of something. When      the rebel ships are being chased by the First Order, they appear to stay the same distance from the ships after initially moving out of effective range.    The only way this makes sense with both distance and fuel burning is if they are accelerating at the same rate. At some point I believe someone says the Resistance ships are faster (I am assuming this refers to acceleration, because neither fleet should have a terminal velocity other than the speed of light), so I suppose they were only accelerating as fast as the First Order to save fuel, and had determined they were not sufficiently fast to totally outrun the First Order.   However, I find it hard to believe that two fleets could accelerate, near the maximum capacity of one of them, for at least 18 hours and not go into hyperspace. These are ships that can traverse systems in minutes if they choose, and I find it equally hard to believe that the First Order would only use a fraction of their available power in pursuing the rebels. How then were the rebels able to run out of fuel without changing their velocity significantly?


Question Regarding Possessives with ('s) and (of)

Question: Is the first one redundant and proper, or is it redundant and not necessarily correct?  (1) He is a friend of Doug's. (2) He is a friend of Doug.


Two non-isomorphic modules that are isomorphic groups

Can you give me a concrete example of two modules over a ring $R$ that are not isomorphic , but that are isomorphic as abelian groups.  I know that this question was posted here before, but the answer given was not a concrete example and I would like to see one.


I am trying to make a 'switch' in python, the function that the code is on loops infinity and i want to make a switch so that when the conditions are met they will not be rechecked.   I've tried putting def chosen(): outside of the looping functions and calling it but it won't run.  def chosen():     if 815 + 70 > mouse[0] > 815 and 115 + 70 > mouse[1] > 110:         pygame.draw.rect(view, gray,(815,115,70,70))         if pygame.mouse.get_pressed() == (1,0,0) and 815 + 70 > mouse[0] > 815 and 115 + 70 > mouse[1] > 115:                 return "redcav1"                 pygame.draw.rect(view, gray,(815,115,70,70))         elif 815 + 70 > mouse[0] > 815 and 215 + 70 > mouse[1] > 215:             pygame.draw.rect(view, gray,(815,215,70,70))             if pygame.mouse.get_pressed() == (1,0,0) and 815 + 70 > mouse[0] > 815 and 215 + 70 > mouse[1] > 215:                  return "redcav2"  if chosen() == "redcav1":     pygame.draw.rect(view, gray,(815,115,70,70)) elif chosen() == "redcav2":     pygame.draw.rect(view, gray, (815,215,70,70)) else:     chosen() print chosen()   I expect it to work like a light switch but it works like a button only working while pressed.


using inotify to monitor access to a file

I would like to have a trigger and when a particular file is accessed by some process, I would like to be notified (i.e. a script should be run). If I understand correctly, this could be achieved with inotify.  If I have a file /foo/bar.txt how would I set up inotify to monitor that file?  I am using Debian Wheezy with kernel 3.12 (my kernel has inotify support)


Easiest fix for this transmission problem?

My bike is an adult mountain bike with different gear shifts and all.   Suddenly my rear tire stopped going but the chain and everything still works - the gear and chain still spins.  What is the easiest way to fix the rear chain/cog if it's not turning the rear wheel?


How to evaluate this trigonometric limit?

I have been struggling to solve this limit.  What is the limit as $x$ approaches $45^0$ of $$\frac{\sqrt{2}\cos x-1}{\cot x-1}?$$   I know how to use L'Hospital's rule to calculate this limit and got the answer as $0.5$. But, how do I calculate the limit by manipulating the function? Please provide only some hints to proceed.


Biblatex: Print author names in reference list for non-unique authors

My references contain two elements with the same author names and year in them. Using style=authoryear, they are listed as "Authors, 2009a" and "Authors, 2009b" in the text which is fine for me. However, In the reference section, the author field of the second entry seem to be replaced with an em-dash (—). I already tried to find a corresponding field that I can change with \DeclareFieldFormat, but had no luck. How can I change this so that both entries list the author names. Example output:  And this is how I want it to be (note how both entries for Alam, A. have full author information):  Example code: \documentclass{article}  \usepackage{filecontents} \usepackage{hyperref}  \begin{filecontents*}{mybib.bib} @article{alam2009a,   title = {High-Resolution Structure of the Open {{NaK}} Channel},   author = {Alam, Amer and Jiang, Youxing},   date = {2009-01-21},   journaltitle = {Nature Structural \& Molecular Biology},   volume = {16},   pages = {30--34},   doi = {10.1038/nsmb.1531},   keywords = {\#nosource},   number = {1} }  @article{alam2009b,   title = {Structural Analysis of Ion Selectivity in the {{NaK}} Channel},   author = {Alam, Amer and Jiang, Youxing},   date = {2009-01},   journaltitle = {Nature Structural \& Molecular Biology},   volume = {16},   pages = {35--41},   doi = {10.1038/nsmb.1537},   langid = {english},   number = {1} }  @article{altomare2001,   title = {Integrated {{Allosteric Model}} of {{Voltage Gating}} of {{Hcn Channels}}},   author = {Altomare, Claudia and Bucchi, Annalisa and Camatini, Eva and Baruscotti, Mirko and Viscomi, Carlo and Moroni, Anna and DiFrancesco, Dario},   date = {2001-06-01},   journaltitle = {The Journal of General Physiology},   shortjournal = {J Gen Physiol},   volume = {117},   pages = {519--532},   number = {6}, } \end{filecontents*}  \usepackage[     style=authoryear,     doi=false,     backref,     giveninits=true,     uniquelist=false, ]{biblatex} \addbibresource{mybib.bib}  % newline after author and year \DeclareDelimFormat[bib]{nametitledelim}{\newline\bibsentence}  \begin{document} This is a document that cites \cite{alam2009a} and \cite{alam2009b} and has a reference from \cite{altomare2001}. \printbibliography  \end{document}


How do I create a hinged door that opens and closes in Blender? If I knew how to do this, then it would help me also create moving control surfaces on model aircraft, such as the rudder and horizontal stabilizers.


Using Comparable interface in parent class without implement compareTo cause error in child classes but not in Parent class ¿Why?

As I said in title, I'm creating a parent class implementing Comparable interface in it but without implement compareTo() method and this is causing an error in child classes but not in Parent class ¿Why?  This is a sample:  public abstract class EarthquakeMarker extends CommonMarker implements Comparable<EarthquakeMarker> { // I know that I need to implement compareTo() here }   My child classes are:  public class LandQuakeMarker extends EarthquakeMarker { }  public class OceanQuakeMarker extends EarthquakeMarker { }   Both child classes are  complaining about the implementation of compareTo() method. I want to know why this error appears in child classes instead of the parent class which is the class that's using the comparable interface


Who is the future "us" that Cooper mentioned while he was in the black hole?

While Cooper was in the black hole at the end of Interstellar, TARS mentioned that the walls (which is a 3D space in 5D) were up put by "them" (some other higher form of being) and Cooper replied that is was actually put up by future 'us'.  So there is 2 possibilities for this case,   'they' is some other higher form of being who mastered 5D apart from humans. 'they' is the future "us" which can be the embryos which Dr.Brand developed on Edmunds's Planet or us itself.   In first case, there are no complications that the future us is some other higher forms other than humans who put the tesseract in the black hole so that the entire human race could exist.  In second case, if the embryos is our future then there is a complication.  Embryos traveled to other galaxy with the help of Cooper, so when Cooper fell into black hole the embryos didn't even reach the other planet. So how did they put the tesseract in the black hole and for sake we can tell that time is moving very slowly in the black hole so the embryos got the time to get developed and put the tesseract in the black hole, so that he could transmit the quantum data inside the black hole which can crack the gravity equation and send him the Nasa co-ordinates. Now here we again have the controversy, if Cooper is sending the location of Nasa now (while in the black hole), how come initially he came to the black hole (this is a time paradox)?  So my simple question is how did our future survive such that it came back to past for saving the existing human civilization?


Trigger the final bibliography from the beginning

I'd like to add at the top of a .tex file a line to enable a command placed at the bottom of it (for instance, \printbibliography)  Why ? Firstly, in order to make easily disable this command in a very long .tex file. Even better, in order to externalise this line in a template input file, called at the beginning of the compiling process.  I've already tried to redefine the command \end{document} to adding \printbibliography before, like that :  \newcommand{\end{document}}[1]{\printbibliography \end{document}}}   But it doesn't work (it would have been too simple).  Here is an MWE :  \documentclass{article}  \usepackage{filecontents} \begin{filecontents}{\jobname.bib} @article{Bob1996,   title = {A {{Very Nice Title}}},   volume = {10},   number = {2},   journaltitle = {Annual Review of Nothing},   date = {1996},   author = {Bob, Bob} } @article{John1996,   title = {A {{Nice Title}}},   volume = {10},   issue = {2-3},   journaltitle = {Annual Review of Something},   date = {1996},   author = {John, John} } \end{filecontents}  \usepackage{biblatex}     \addbibresource{\jobname.bib}   % What I tried : % \newcommand{\end{document}}[1]{\printbibliography \end{document}}}  \begin{document}  ... A long long long text...  % Here is the command I need to remove, without removing  % the bibliography itself in the output file : % \printbibliography  \end{document}


Help with making a large print - 60 x 36 - will my photo work?

I would like to make a very large print of a photo I have taken, of about 60 inches wide, and about 36 inches high (though the actual aspect ratio of the cropped file would imply a 34 in height).  The size of the image is 4858x2733 pixels.  Is it possible to make a print of that size and have it look okay without additional post processing?  What's the largest print I could comfortably make without printing on canvas?  Thanks so much, Tom


How to interpolate daily climate data using ArcGIS for Desktop?

I want to interpolate daily climate data available from 3 locations. I am not sure how to interpolate the data for daily values for 30 years from the available 3 locations.


If R is a commutative ring with identity that has exactly three ideals 0, I and R. Show that if a does not belong to the I then a is unit R.


I wondered, if $\forall x\, \exists y\, R(x,y)$ is equivalent to $\exists y\, \forall x\, R(x,y)$.  If $R(x, y) = (x < y)$ then the answer would appear to be no.   In the first case, for all $x$, does there exist a $y$ such that $x < y$? Sure, just pick $y = x + 1$.   In the second case, it says there exists a $y$ such that $x < y$ holds for all $x$. But any $x$ that is greater than or equal to $y$ would make this false.  So it seems that the order of the quantifiers matter, but then we have this proof:  ∃x ∀y R(x, y)                                 [Hypothesis]  Let c be a constant such that ∀y R(c, y)     ∀y R(c, y)          Given constant d:         R(c, d)                               [∀ elim]         ∃x R(x, d)                            [∃ intro]      ∀y ∃x R(x, y)                             [∀ intro]  ∀y ∃x R(x, y)                                 [∃ elim]   Here it seems to imply we can swap the order if we start out with an exists quantifier coming first?  In other words is it true that:  $\forall x\, \exists y\, R(x,y) \not\rightarrow \exists y\, \forall x\, R(x,y)$ (how would we actually prove this?)  But:  $\exists y\, \forall x\, R(x,y) \rightarrow \forall x\, \exists y\, R(x,y)$


How Newton's third law is involved in a tug of war?

Using Newton's third law, we can say that each team applies the same force on the opposite team. Then how one wins?  Is it due to ground friction?


I am trying to install the desktop environment of lubuntu on Ubuntu 18.04.02 but I am getting the following error:  $ sudo apt install -y lubuntu-desktop Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  lubuntu-desktop : Depends: lubuntu-gtk-core but it is not going to be installed                    Depends: lubuntu-gtk-desktop but it is not going to be installed E: Unable to correct problems, you have held broken packages.   Any idea how to address this?


Suppose that $f:[0,\infty)\to\Bbb R$ is differentiable, and $\lim_{x\to\infty}(f(x)+f'(x))=0$. Prove that $\lim_{x\to\infty}f(x)=0$.  I tried to show that $\lim_{x\to\infty}f(x)\neq0\rightarrow \lim_{x\to\infty}(f(x)+f'(x))\neq0$  If $\lim_{x\to\infty}f(x)\neq0, \exists e>0, \forall N\in\Bbb N, \exists x_1, x_2, ...>N,|f(x_i)|\ge e$.  So that the possibility for  $\lim_{x\to\infty}(f(x)+f'(x))=0$ is only when $f(x_i)+f'(x_i)=0$ is true for any $i$.  So if  $f(x_1)\gt0,$ it must be decreasing, to less than $e$  But there exists $x_2\gt x_1 s.t. |f(x_2)|\ge e$  In conclusion, $f(x)$ has to decrease when $x$ is large enough and $f(x)\ge e$ but there must exists infinitely many points whose function value is no less than $e$. But it cannot happen.  Is my idea of proof valid?  I don't know how to formally write my idea...please teach me..


How did "September" shift from 7th month to 9th month of a year? (and same for October, November, December)

If I understand correctly, the words September, October, November and December all come from French counterpart Septembre, Octobre, Novembre and Decembre, and ultimately from Latin septem, octo, novem and decem with a suffix -bre. Therefore I suppose their original meaning were from "7th month of a year" to "10th month of a year".  Apparently those words stand for "9th month" to "12th month" nowadays, so why and how did this happen?


Which one is the grammatically correct sentence? 1) watch the television. 2) watch television.


Is the function $(x^2+y^2)\sin\frac{1}{x^4+y^4}$ differentiable at point $(0,0)$

The function is defined as $$f(x,y)=\left\{\begin{array}{ll}(x^2+y^2)\sin\frac{1}{x^4+y^4}&(x,y)\ne(0,0)\\0&(x,y)=(0,0)\end{array}\right.$$ How do I find out if the function is differentiable at point $\;(0,0)\;?$ At first it's clear that the function is continuous, because limit at $(0,0)$ is the same as value of function at $(0,0)$. It's also clear that the function is differentiable in all $(x,y)\ne(0,0)$. Now it's only left to figure out the differentiability at $(0,0)$. My take on it was that we know how does a total differential of a function looks like $$df=\frac{\partial f}{\partial x}dx+\frac{\partial f}{\partial y}dy$$ so we need to check if the partial derivatives at $(0,0)$ exist. From definition we have $$\frac{\partial f}{\partial x}(0,0)=\lim_{x\to0}\frac{f(x,0)-f(0,0)}{x-0}=\lim_{x\to0}\frac{f(x,0)}{x}=\lim_{x\to0}\frac{x^2\sin\frac{1}{x^4}}{x}=\lim_{x\to0}\left(x\sin\frac{1}{x^4}\right)=0$$ Same goes for partial derive with respect to $y$. Am I correct, if now I conclude that the function is differentiable at $(0,0)$ or is there something else that needs to be done?


I have a command line execution in my .sh file which unzips the file which is in zip format. Below is the command which unzips the file unzip -p -a.  elif [ "${FILECOMMANDOUTPUT}" = "Zip" ] then  COMMANDTOUSE="/usr/bin/unzip -p -a"   But if the file size is larger (say 935 MB) the above command unzip -p -a is not working. I've got 7z e -so -bd command which works if we need to pipe or redirect the output of it somewhere else (to a file) . But I just need a single command which can replace unzip -p -a in the above code.


Let the matrix $T_n\in M(n\times n,\mathbb{F})$, where $\mathbb{F}$ denotes a field, be defined by $T_n=(t_{ij})$ with  $$t_{ij}= \begin{cases}        \alpha\beta &  1\leq i\leq n-1,\;j=i+1 \\       \alpha+\beta & 1\leq i\leq n,\; j=i \\       1 & 2\leq i\leq n,\; j=i-1 \\       0 &\textrm{otherwise}    \end{cases} $$  Show that  $$\det(T_n)=\sum_{k=0}^{n}\alpha^{n-k}\beta^k$$    My approach: I tried a proof via induction and while the basis step is trivial, I can't seem to solve the induction step since the matrix is never in upper or lower triangular form but always a block matrix, which makes this seemingly difficult as when calculating the determinant of block matrices, one usually calculates the product of all the "diagonal blocks".  I would very much appreciate help, thank you very much.


Why do we always see the same side of the Moon?

I am puzzled why we always see the same side of the Moon even though it is rotating around its own axis apart from revolving around the earth. Shouldn't this only be possible if the Moon is not rotating?


No Icons or menubars visible in Ubuntu 13.10

I'm unable to see any icons or menubars on my desktop. However, I am able to open up the file/folder explorer by inserting a USB, which opens up the explorer and let's me open applications and files    However, some applications are visible without the menubar on top, i.e. I can't close them. Additionally, I cannot search for terminal- no results show up. I found terminal in my usr/share/app-install/desktop directory, but am unable to open it    I also can't open it using CTRL+ALT+T. So far, I've been able to work and open some files, folders, and applications, but the lack of icons is problematic. Any ideas as to what the problem is?  This is Ubuntu 13.10  -Thanks for reading


Can the boundary of a set be ignored, when integrating over it.

I'm confused whether the following statement is true: Let $K$ be a compact, orientable manifold of dimension $n$ with boundary and $\omega$ be a smooth $n$-form on $K$. Say for example $K$ is the closed unit disc in $\mathbb{R}^2$ and $\omega$ is any $2$-form on $\mathbb{R}^2$ restricted to $K$. Is the following statement true?: $$  \int_{K} \omega = \int_{\overset{°}{K}} \omega $$ , where $\overset{°}{K}$ is the interior of $K$.  I.e. can the boundary of a set be ignored when integrating over the set ? I think it should be true, since the boundary should be a set of measure zero in $K$, but is there a flaw with this reasoning ? Thanks for your help.


How do I make a word possessive when there are words after it before the object?

Would I say: "It was the boy's beside her balloon."  Or  "It was the boy beside her's balloon."  I feel like it's the first one, but it sounds weird when I say it out loud.  Thanks!


Arduino Nano: How to decide voltage divider values that are safe for the input of the ADC

I am building a simple voltmeter circuit that needs to measure up to about 35 volts.  Looking around the web, I am finding all sorts of suggestions for voltage divider values, like 1 Mohm / 10 Kohm, and the one I am currently experimenting with, which is 10K/2K.  I am having issues with allowing enough time between readings for the Arduino Nano to settle down, of course, but that is not the question.  Using 10K/2K it maxes out at a reading of 1020 on A6 with an input of 27 volts.  I do not understand why one posting says to use resisters in the Mohm range and the other (that I am using) is a total of 12k.  Question:  Is there a rule of thumb that should be used to decide what resistances should be used for the divider for measuring this level of voltage?   And how important might it be to keep the resistance between Vcc and GND higher than what I am using?   -- EDIT:  EE asked me if this was the same as another suggested Q/A - and this is only different because it is specific to the Arduino's ADC input impedance.  The other answer only talked about the ratios.    The answers to this are great for my particular application.    --FURTHER EDIT:  Based on the collective berating from the powers that be, I would mention that this started in an Arduino forum where I was concerned about the particular ADC, then it got moved here.  Calling this a duplicate is incorrect.  It is very specific to the Nano application.  I wanted to make sure my small values wouldn't cause problems by being between Vcc and GND.  Plus, I did not know the proper input impedance for the Nano's ADC.  It all got answered here, nicely.  Thus I believe it stands as being unique here.  I can find no duplicates of this particular question.  Being marked this way with no explanation is frustrating.  If there really are duplicates then I would like to see their answers.  But finding none, this one adds to the community and I believe it should not be marked as a duplicate here.  And the good thing is that one respondent brought up smoothing capacitors.  So now I am using one, and it helps stabilize the readings.  So this has been a positive experience.  The problem now is that Arduino people won't necessarily know to look here for this answer when they try to use their Arduinos this way.  So there will likely be duplicate questions there which just got answered here.


So I have this problem where I want to get the filename and insert it into a cell in excel but I need a specific word to be inserted in the excel, right after the "_". For example, the excel file is 01 Monthly report_January.xlsx so the filename inserted to the cell should be January excluding the file type eg. xlsx, xls. How to achieve this? The filename is from the currently opened excel.


I lost my USB bluetooth dongle (from DEll) which I used for a wireless  mouse. kindly provide solution


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?


ASP.Net URLEncode Ampersand for use in Query String

I need to redirect to a url passing a parameter as a query string.  This can include an Ampersand in the value. such as  string value = "This & That"; Response.Redirect("http://www.example.com/?Value=" + Server.UrlEncode(value));   This however returns   What should I be using to encode this string?  EDIT: Thanks Luke for pointing out the obvious, the code does indeed work correctly. I Apologise, my question was not a valid question after all!  The page I was going to had a lot of old legacy code which is apparently doing some kinda of encoding and decoding itself making it appear as if my urlencode was not working.  My solution unfortunately is to completely drop use of an & until the code in question can be re-written. Don't you just hate old code!


I'm a newbie to Linux using Ubuntu 16.04 and my manager ask me to upgrade my system to 17. So I need your help to guide me how to upgrade my system to 17.


C# - Is there a way to call a static method of a generic type in a class?

Example:  Public class a<T> where T: containsStatic {     public void func()     {         T.StaticMethod();     }  }   Is it possible? And if not is there another way to do it?  EDIT:  it gives me the error: "'T' is a type parameter, which is not valid in the current context." why is that? is there a way to fix this?


How to prove $\lim_{n \to \infty} \sqrt{n}(\sqrt[n]{n} - 1) = 0$?

I want to show that $$\lim_{n \to \infty} \sqrt{n}(\sqrt[n]{n}-1) = 0$$ and my assistant teacher gave me the hint to find a proper estimate for $\sqrt[n]{n}-1$ in order to do this. I know how one shows that $\lim_{n \to \infty} \sqrt[n]{n} = 1$, to do this we can write $\sqrt[n]{n} = 1+x_n$, raise both sides to the n-th power and then use the binomial theorem (or to be more specific: the term to the second power). However, I don't see how this or any other trivial term (i.e. the first or the n-th) could be used here.   What estimate am I supposed to find or is there even a simpler way to show this limit?  Thanks for any answers in advance.


How to apply for a Schengen visa if I don't have payslips from the last 3 months?

I just started a LLC (limited liability company) and I'll be receiving my first pay slip next week, and I want to apply for a Schengen visa, can't I apply for the visa with 1 or 2 slips?  . You can load the English version as well


Would be nice to be able to follow a question with a single click. Right now I use a workaround solution that takes a few clicks (if I can remember the way to do it at all)


How to hide formula results in a cell until conditions are met - percentage discount

My question relates to this post, but with different formula criteria: .   Here's the setup for a spreadsheet to calculate the percentage discount for various staff based on their hourly rates:   Row D = regular $ rate for staffperson Row E = discounted $ rate for staffperson Row F = percentage % discount for staffperson   I would like to calculate the percentage difference in row F (I have the formula set up there) but I do not want anything to appear in the Row F's cells unless a discounted rate is entered in a Row E cell for a specific staffperson.  Currently, the way I have it set up, I always have values entered in the Row D cells since the regular rates do not change, but depending on the agreement with a client, I will often modify the discounted rate cells in Row E to reflect different discounted rates.  I would only like to see the percentage discount in a Row F cell if a value were entered in Row E for certain staff.  Thanks for any suggestions.


CLI options do not work if passed at the end of command

In brief: ls -a /tmp works but ls /tmp -a does not.  I recently started using Macbook Pro. Coming from a Linux background, command like ls /tmp -a seems perfectly fine to me.   But for some reason these do not work in the same fashion in Mac. Argument flags are not recognised if they are specified at the end after the path.   Here is a demo:  /tmp/demo  ➜ ls -a ./ .           ..          .hidden-bar foo /tmp/demo  ➜ ls ./ -a ls: -a: No such file or directory ./: foo /tmp/demo  ➜        I am using latest zsh 5.0.5 (x86_64-apple-darwin14.0)  I can see similar behaviour of several other commands like du, rm etc. Almost all such are in /bin folder. I wonder if it has something to do with UNIX and Linux differences.  Does anybody know the reason behind the difference and if possible a fix for it?


Non-existence of bijective, continuous function from $(0,1)$ to $[0,1]$

The problem : Give example of a continuous, onto function from $(0,1)$ to $[0,1]$. Is it possible for such a function to be one-one? My partial solution : For the $1^{st}$ part of the question, I came up with this example - $f : (0,1) \to [0,1]$ given by $f(x)=\sin\big({2\pi x}\big)$ This is continuous and onto, but not one-one. What I'm asking : For the $2^{nd}$ part of the question, I feel that it should be provable that there cannot exist a continuous, onto, one-one function from $(0,1)$ to $[0,1]$ (If not, we need a counter-example). Any help regarding this proof (or what would really surprise me, a counter example)? Thanks in advance.


Breaking my rejection of christianity to my parents

I know this isn't exactly appropriate for this site -- I'm not a parent, I'm a son -- but I think it's still applicable to the community here. I would prefer feedback from actual parents concerned about other parents, not people who theorize about child-parent relationships, but if there's a better q/a site for me to migrate this question to, please let me know.  I am 20 years old, third year in college. I went to church about every Sunday for the first 18 years of my life, with my parents. When I moved out to go to college, I stopped going to church all together. My Mom still tells me every time I see her (whenever I go home, about twice a semester) that she's praying for me. I go with my parents to church every time I'm home, sing the songs, pray the prayers at dinner, the whole deal. Both my parents ask me if I've found a church yet, how often I go looking, etc. but I always manage to give them the excuse that I've been really busy with school (which is true, but of course irrelevant).   The truth is, I haven't self-identified as a christian since I was 16. I've avoided telling my parents this because... well, it would be very difficult. My Mom would probably get really upset and my Dad would probably just try to get in a huge theological argument with me, but it wouldn't change my mind, it would distress them further, and lead to a large divide between us. At the same time, it feels wrong to outright deceive them all the time. I'm definitely willing to continue whatever traditional religious stuff I would otherwise do to please them, even though it all means nothing (other than family tradition) to me.   As a parent, can you give me some advice on what to do? Should I have the talk and break it to them? If so, what's the best way to do that? How can I avoid religion causing a divide between us?


I receive this message when trying to open Netflix Desktop.  Compositing is not available, please enable compositing support and relaunch Netflix Desktop.  How do I enable compositing support for Netflix?


Web utility for viewing $x$-$t$, $v$-$t$, and $a$-$t$ graphs

I'm wondering if there exists any utility on the web which displays $x$-$t$, $v$-$t$, and $a$-$t$ graphs for, say, a number of well considered example animations. The utility should allow pausing, rewinding, replaying, and 'stepping' through the animation. When playing the animation, it should 'highlight' the current time on the d,v, and a graphs.  Etc etc. I'm sure you have an idea what I'm after - searches online have mostly led me to lectures and lessons explaining the relationship between the three graphs.


I read in a book "Physics - Resnik and Halliday" the explanation of Type-I Superconductors {cold ones} that:  The Electrons that make up current at super-cool temperatures move in coordinated pairs. One of the electrons in a pair may electrically distort the molecular structure of the superconducting material as it moves through, creating  nearby short-lived regions of positive charge.the other electron in the the pair may be attracted to the positive spot. According to the theory the coordination would prevent them from colliding with the molecules of the material and thus would eliminate electrical resistance  Is this the only explanation or can somebody give me a more intuitive explanation that also takes into the problem of defect scattering as in the case of resistance and also explains the Type-II superconductors {hot ones} P.S. What are "coordinated pairs"?


Do the polynomials $(1+z/n)^n$ converge compactly to $e^z$ on $\mathbb{C}$?

The question is     Do the polynomials $p_n(x)=(1+z/n)^n$ converge compactly (or uniformly on compact subsets) to $e^z$ on $\mathbb{C}$?   I thought about expanding $$p_n(z)=\sum_{k=0}^n a_k^{(n)}z^k$$ where $$a_k^{(n)}=\binom{n}{k}\frac{1}{n^k}=\frac{1}{k!}\prod_{j=0}^{k-1}\left(1-\frac{j}{n}\right)$$ and trying to show that $\frac{1}{k!}-a_k^{(n)}$ decreases sufficiently fast on any closed ball. That is, I tried to show $$\lim_{n\rightarrow\infty}\max_{z\in\overline{B_0(A)}}\left|\sum_{k=0}^n\frac{z^k}{k!}-p_n(z)\right|=0$$ for any fixed $A>0$, but I had difficulty with this approach.  Any help is appreciated.


The lines on the Reputation graph's area selector are invisible in Chrome

This concerns the graph view on the reputation tab of your profile. (i.e. )  In Chrome, the area selector doesn't show its bars.  Something similar appear to have been reported , but this is a completely different one. This isn't solved by returning to default zoom - in fact, the bars are somewhat visible in any zoom level except for the default one.  Firefox 26:    Chrome 32:    (Note the absence of the little spikes along the bottom row, or that specifically, they're white.)


Let $f:K\to K$ with $\|f(x)-f(y)\|\geq ||x-y||$ for all $x,y$. Show that equality holds and that $f$ is surjective.

$K$ is a compact subset of $\Bbb R^n$ and $f:K\rightarrow K $ satisfies :  $$\|f(x)-f(y)\|\geq \|x-y\|$$  Show that $f$ is bijective, and that : $$\|f(x)-f(y)\| = \|x-y\| $$  It's easy to show that $f$ is injective. But I can't think of a way to prove surjectivity.


Computing $\lim\limits_{n\to\infty} \int_{0}^{\infty}\frac{\sin(x/n)}{(1+x/n)^{n}}\, dx$

$$\lim_{n\to\infty} \int_{0}^{\infty}\frac{\sin(x/n)}{(1+x/n)^{n}}\, dx$$  I've been able to show that the integral is bounded above by 1 (several ways). One of the simplest is just letting $u=x/n$ and doing some bounding above. It must converge to something (if it is monotone increasing.. don't think so), but all my efforts to use Lebesgue Dominated Convergence have failed. I can't seem to dominate this function...   However, if I could dominate it the integrand converges pointwise to 0 and so then the integral would be 0, which I think is incorrect.  I have found it sufficient to deal with  $$\lim_{n\to\infty}\int_{0}^{n}\frac{\sin(x/n)}{(1+x/n)^{n}}\, dx$$  I tried to turn it into a series and use the converse of the integral test, but that hasn't went well.  I've used Egoroff's theorem to try to use uniform convergence but that failed.  Some of the inequalities and ideas I've tried to use in a solution include:  $sin(x/n)\leq x/n$  after a $u$ sub I've tried to turn it into a riemann sum... failed  $(1+x/n)^{n}\geq 1+x$ and the binomial theorem  $(1+x/n)^{n}$ converges to $e^x$ and it is increasing in $n$ so $e^{-x}\leq \frac{1}{(1+x/n)^{n}}$  I've tried to use that the integrand is measurable and subtract out different measurable sets from the integral to make it more convenient..   I've been playing with this on and off for a month or so and no luck. I appreciate any help here.  Update: From mixedmath's suggestion  splitting it into $[0,10]$ and $[10,\infty]$ it is clear that the integrand is dominated on $[0,10]$ (say by 1) and so lebesgue sends that portion to 0.  On the larger interval I am still running into a problem making it bounded nicely. If I try a $u$ sub the bounds get messy. I would like to choose an $n$ so that   $2e^{-x} \leq (1+x/n)^n$ for all $x\in [10,\infty]$ .. maybe:  there exists an $N$ such that for all $n\geq N$  $e^{10}/2 < (1+10/n)^{n}$   but for $x>10$..  $e^{10}/2<(1+10/n)^{n}<(1+x/n)^{n}$  but that's not quite right..


How would I design an S-R flip flop under these given conditions?

Given an AND gate, an OR gate, and inverters as needed, design an SR flip flop with S and R active low (0).   I understand that to make such a flip flop, I would have to place inverters on the circuit so that the AND and OR gates behave like NOR gates, as NAND with S=0, R=0 would lead to a race condition. However, I have no idea how I would place inverters in such a way for it to behave like NOR gates.


search only the current directory on key press in ubuntu 13.04

I am currently using 13.04. Till 12.10 in file browser (nautilus) pressing any key press will select the directory starting with that key. For example when i do the below   Opening a nautilus  Press D (all folder that starts with D will be selected and not the subfolders)   Whereas in ubuntu 13.04 it searches all the folders in the current directories and in sub directories too.   Is it possible to restrict the search only to current directories by any configuration. Thanks for your guidance.


I commited a new log entry with:  git commit -am "newLogEntry"  Now I want to change the name of my last log entry... (overwriting the last one).  How can I do that? What is the code for that in Git?


I need help with this proof:  $f: X\rightarrow Y$  $C,D\subseteq Y$  $f^{-1}(C \cap D) = f^{-1}(C) \cap f^{-1}(D)$  Thanks.


Do not 'Auto Hide' dock on Cinema Display

I have my dock preferences to auto-hide. When I plug in my Cinema Display it works as expected: the dock hides when the mouse isn't hovering over it. Is it possible to disable this functionality ONLY on the Cinema Display and keep it happening on the macbook?  For clarification: When my cinema display is plugged in I should be able to see the dock at all times on my cinema display, but it should still auto hide on macbook screen.


Stripboard/veroboard/matrix board design software

I'm prototyping a simple layout for a small project on matrix board, but figured there must be a better way than drawing it all out on paper. Are there any aimed at matrix board?  I've found the following software for stripboard, but nothing explicitly for matrix board:     Stripboard Magic (seems to be abandonware, but there's page about it )  Stripboard Editor Limited free version, designed to integrate well with     Any more I've missed? Any recommendations?


I Want to know how to design good class A amplifier of 10W for 8ohm load. with common emitter stage for input and emitter follower for output.with minimum component quantity.first stage is below Vc is about 12.34V and Ic is 6mA maximum 10 mA. I have 25 v 4A supply please help with detail.


Prove that $$\sum_{k=0}^{n}{\binom{2k}{k}\binom{2n-2k}{n-k}}=2^{2n}$$  I was having trouble with this one because all four of the indexes are varying here. So I tried to think of a combinatiorial argument, but wasn't quite able to tie everything together. I was thinking along the lines of imagining $2n$ elements which were separated into $n$ pairs, and then partitioned into two subsets (total $2^n$ subset combinations possible). How should I proceed? (PS no proofs using induction please)


How to know the distance of the black hole merger?

I have a question about the detection of the gravitational waves by LIGO. When there is no electromagnetic wave coming from the black holes, then how do they know in which distance it is?


How to print both matching lines from two different files?

I have file1 and file2 as following. I would like to first find matches between two files based on first column and then print the matching lines from file1 and file2. I have written the desired output below  $ cat file1 1,      456,    abcd,  ... 23,     567,    rstc,  ... 45,     678,    rsto,  ...     $ cat file2 23,     5607,   abcstc, ... 45,     28,     zfgsto, ...   Desired output:  23,     567,    rstc,    ... 23,     5607,   abcstc,  ... 45,     678,    rsto,    ... 45,     28,     zfgsto,  ...


Logic problem: Identifying poisoned wines out of a sample, minimizing test subjects with constraints

I just got out from my Math and Logic class with my friend.  During the lecture, a well-known math/logic puzzle was presented:  The King has $1000$ wines, $1$ of which is poisoned.  He needs to identify the poisoned wine as soon as possible, and with the least resources, so he hires the protagonist, a Mathematician.  The king offers you his expendable servants to help you test which wine is poisoned. The poisoned wine is very potent, so much that one molecule of the wine will cause anyone who drinks it to die.  However, it is slow-acting.  The nature of the slow-acting poison means that there is only time to test one "drink" per servant. (A drink may be a mixture of any number of wines)  (Assume that the King needs to know within an hour, and that any poison in the drink takes an hour to show any symptoms) What is the minimum amount of servants you would need to identify the poisoned wine?  With enough time and reasoning, one can eventually see that this requires at most ten ($10$) servants (in fact, you could test 24 more wines on top of that 1000 before requiring an eleventh servant).  The proof/procedure is left to the reader. My friend and I, however, was not content with resting upon this answer.  My friend added the question:  What would be different if there were $2$ wines that were poisoned out of the 1000?  What is the new minimum then?  We eventually generalized the problem to this:  Given $N$ bottles of wine ($N \gt 1$) and, of those, $k$ poisoned wines  ($0 \lt k \lt N$), what is the optimum method to identify the all of the poisoned wines, and how many servants are required ($s(N,k)$)?  After some mathsing, my friend and I managed to find some (possibly unhelpful) lower and upper bounds: $ log_2 {N \choose k} \le s(N,k) \le N-1 $ This is because $log_2 {N \choose k}$ is the minimum number of servants to uniquely identify the $N \choose k$ possible configurations of $k$ poisoned wines in $N$ total wines. Can anyone help us find an optimum strategy?  Besides the trivial one requiring $N-1$ servants.  How about a possible approach to start? Would this problem be any different if you were only required to find a strategy that would for sure find a wine that is not poisoned, instead of identifying all poisoned wines? (other than the slightly trivial solution of $k$ servants)


I'm trying to populate the sum(total selling price)of child object on to the "total order item value"{currecny data type field} of parent object. Here is the code  trigger Rollup on OSF_Order_Items__c (after delete,after insert,after update,after Undelete) {  set<Id>OpportunityIds=new set<Id>(); if(trigger.isInsert || trigger.isUpdate || trigger.isUnDelete){ for(OSF_Order_Items__c o:trigger.new){ OpportunityIds.add(o.Opportunity__c); } } if(trigger.isDelete) { for(OSF_Order_Items__c o:trigger.old){ OpportunityIds.add(o.Opportunity__c); }} Map<Id,Double>OpportunityMap=new Map<Id,Double>(); for(AggregateResult q:[select Opportunity__c,sum(Total_Selling_Price__c)from OSF_Order_Items__c where Opportunity__c IN:OpportunityIds group by Opportunity__C]){ OpportunityMap.put((Id)q.get('Opportunity__c'),(Double)q.get('expr0')); } List<Opportunity>OpportunitiesToUpdate = new List<Opportunity>(); for(Opportunity o:[Select Id,**convertcurrency(Test_Total_Order_Item__c)** from Opportunity where Id IN:OpportunityIds]){ Double Item =OpportunityMap.get(o.Id); o.Test_Total_Order_Item__c=Item; OpportunitiesToUpdate.add(o); } update OpportunitiesToUpdate; }   Problem: The vaule which was returned was not coorect. for example the value expected is USD 15,561 AND result is USD 11335. I observe 11335 is and euro euivalent of 1556l. my org currency is euro.  i want to display the sum of child along with userdefined currency on to the parent as it is. any luck?


Prove the representation of complex numbers is parallelogram

Question :  Let $z_1,z_2,z_3,z_4$ be the position vectors of the vertices for quadrilateral $ABCD$. Prove that $ABCD$ is a parallelogram if only if $z_1-z_2-z_3+z_4=0$  What i've done so far :  Proof of $p\Rightarrow q$  Let $z_1=x_1+iy_1,\quad z_2=x_2+iy_2, \quad z_3=x_3+iy_3, \quad z_4=x_4+iy_4$  $ABCD$ is a parallelogram $\Leftrightarrow\,\overrightarrow{AB}=\overrightarrow{CD}\, \land\, \overrightarrow{AD}=\overrightarrow{BC} $   $\begin{aligned} \overrightarrow{AB}=\overrightarrow{CD} &\Rightarrow |z_1-z_2|=|z_3-z_4|\\ &\Leftrightarrow x_1^2-2x_1x_2+x_2^2+y_1^2-2y_1y_2+y_2^2=x_3^2-2x_3x_4+x_4^2+y_3^2-2y_3y_4+y_4^2\\ \overrightarrow{AD}=\overrightarrow{BC} &\Rightarrow |z_1-z_4|=|z_2-z_3|\\ &\Leftrightarrow x_1^2-2x_1x_4+x_4^2+y_1^2-2y_1y_4+y_4^2=x_2^2-2x_2x_3+x_3^2+y_2^2-2y_2y_3+y_3^2 \end{aligned}$  I'm stuck and see no conclusion here.  Proof $p\Leftarrow q$  I don't have an idea for this.  Please help me, thanks.


Two differents longtable, but same column witdh

I would like to create two differents longtables, with the same width of columns from one longtable to an other other.  Here some specifities.   The longtable have the same number of columns The content of the lastest column have the same size from one header to an other one. Only the content of the first columns could have different size   I would like the size of the first columns be the same from table to an another one, the size should be the max of "autocalculated size".  Here a MWE  \documentclass{article} \usepackage{longtable} \begin{document}  \begin{longtable}{|l|l|} Head & 1 \\ \endhead text & other \end{longtable}  \begin{longtable}{|l|l|} Head & 2 \\ \endhead longer text & other \end{longtable} \end{document}


Can anyone help me in proving that two consecutive numbers are co-primes?  My approach:  Let two consecutive numbers are $n$ and $n+1$.  Assume they are not co-primes.  Then $\gcd(n,n+1)=x$, because it can not equal to $1$, $x$ is natural and $x\gt1$  So $x$ divides $n$ as well as $n+1$.  Then $x$ also divides $n+1-n$, by general understanding.  Hence $x$ divides $1$ or $x=1$.  But we have assumed $x\gt 1$.  So by contradiction $n$ & $n+1$ are co-prime.  Is it right or is there any better way to prove that two consecutive numbers are co-prime?


Creating new empty memory layer with fields scheme from other layer in QGIS?

Being new with python so far, I got inspired by this answer:   to dive into it a bit.  When creating features in a new target layer from an existing source layer, all "solutions" I found so far to create that new layer, were to either   prepare the new target layer manually in QGIS beforehand, adding all fields (with field types, lengths etc). Hard-code the field settings into the python script when creating that new target layer.    It seems a bit odd to me that there should be no programmatic way to clone the attribute scheme of a layer, and create a new (memory) layer with this scheme, so you wont have to change your script for each new layer, or fumble things together manually.  I'm focused on the creation of memory-layers, cause I want to have the opportunity to decide by myself if the outcome is satisfactory and save it manually when it fits my needs.


When a question is put "on hold", I verified three or four times (when my answer was ready), most of the "close" voters seem to be rather older programmers. It's not that I'm interested, but I can see their names and I have already lost time with the answer. Is this a fact? Is up there a council of the elders?


How to use Latex to print a document to look like a lined notebook?

I would like to print a document with text on lined paper like a notebook like   However, I would like to be able to edit the line colours.  I would like to put the header/title in the blank white space. Is there a way to do the document above without using the background jpg?  The document is also multiple pages.   I have looked at this question too and would like to have lines only and not a grid.   Thanks!


Can I use identical names for fields and constructor parameters?

class C {   T a; public:   C(T a): a(a) {;} };   Is it legal?


When any object is dropped onto the material like sand in real life it changes it's surface like it's shown in the photo.    How can I do it in Blender having the object and a subdivided plane that are shown below using physics?   Thanks for help !


How is the degree of the minimal polynomial related to the degree of a field extension?

I was reading through some field theory, and was wondering whether the minimal polynomial of a general element in a field extension L/K has degree less than or equal to the degree of the field extension? i.e.  $deg$(m$_{a}$) $\leq$   $[L:K]$    $\forall$ a $\in$ $L$   If it is true, then could anyone give me an idea as to how to prove this please?


Malformed line in sources.list when updating Ubuntu 20.04 with sudo apt update

在Ubuntu上用sudo apt update进行更新是显示 E: Malformed entry 15 in list file /etc/apt/sources.list (Component) E: The list of sources could not be read. 要怎么解决？ 我是小白，希望能够具体一点，谢谢。  $ sudo apt update E: Malformed line 15 in source list /etc/apt/sources.list (component)  E: The list of sources could not be read.


Are my arguments correct about limit points of $A=${$m+n\sqrt 2:m,n\in \mathbb Z$}?

Let $A=${$m+n\sqrt 2:m,n\in \mathbb Z$},then-      $(1)A$ is dense in $\mathbb R$.      $(2)A$ has only countable many limit points in $\mathbb R$.      $(3)A$ has no limit points  in $\mathbb R$.      $(4)$only irrational numbers can be the limit points of $A$.   $A=${$..,...,-3-3\sqrt 2-2-2\sqrt 2,-1-\sqrt 2,0,1+\sqrt 2,2+2\sqrt 2,3+3\sqrt 2,4+4\sqrt 2,...,...$}  Argument for (1) taking $x=\frac{1}{2}(3+3\sqrt 2)\in\mathbb R-\mathbb A$ taking $\delta=\frac{1}{4}(3+3\sqrt 2)$,then $(x-\delta,x+\delta)\cap A =\phi$.Hence $A$ is not dense in $\mathbb R$  Argument for (2).Since $A$ is not dense in $\mathbb R,$i.e $\bar A\neq \mathbb R,$it means $\bar A $ is either $\mathbb Q$ or $\mathbb Q^c$ or $\emptyset$(please check this point!!!) .Now let us take $q\in \mathbb Q$ and taking $\delta =\frac{1}{4}(m+(n-1)\sqrt 2)$,then $(q-\delta,q+\delta)\cap A=\phi$.Hence $\bar A\neq \mathbb Q$.Hence,$A$ does not have countable many limit points in $\mathbb R$  Argument for (4) taking $x=\frac{1}{2}(3+3\sqrt 2)\in\mathbb Q^c$ taking $\delta=\frac{1}{4}(3+3\sqrt 2)$,then $(x-\delta,x+\delta)\cap A =\emptyset$.Hence,only irrational numbers cannot be the limit points of $A$     Hence the only possibiliy left is $\emptyset$.So, $A$ has no limit   points,making option  (3) true.   Please check my arguments,whether they are correct or not?  Also,please suggest if some improvements can be made  in above arguments  My question is not duplicate of any question.In the suggested duplicate,the proof is given,but i don't want the proof of this,i just want to clarify my concept via this problem regarding limit points,i just wanted to check my arguments,whether they are correct or not...


Since it's currently impossible to delete a "vote to close",* when I see a poorly asked question, should I immediately vote to close, or should I comment, and give the OP a chance to improve his question?  Waiting increases the chance that I'll forget, and never vote to close, potentially leading to a cluttered site.  Voting to close immediately increases the chance that the question will be closed, and the author will be forced to re-post his (hopefully improved) question, which leads to a cluttered site. :)  *It is now possible to , but that doesn't change the fundamental nature of this question.


I have purchased an AB zone Berlin 7 day transport ticket and validated it on Sunday 17th April so hopefully it will be valid until Sunday 24th.  I validated the ticket at about 10:00am so I guess 1000 is the time I validated? But what are the numbers 15 and 6 and letters 'So' correspond to? How (if checked by a guard) can they tell if the ticket is valid? And how can I as a customer tell when it is validated to?


I looked on the internet but couldn't find anything relevant, so I was hoping you could help because I have no clue where to even start with how to solve this equations: x! = 6  Obviously trial and error here could work, but is there any way to do it for examples where trial and error would take too long? Thanks.


Camera and lens settings/preset for iPhone 11 Pro

I've recorded some footage using my iPhone 11 Pro that I want to track. Using Google I found that the primary lens (the one I used) has a focal length of 26 mm. However, I understand that for proper tracking I also need to know the Sensor Width and lens distortion values (K1, K2, K3). I've found some articles that explain how to calculate them, but that's quite a lot of work. Has anyone already calculated these values? Pretty strange that Blender 2.90 doesn't come with presets for recent iPhones. After all I think they're one of the most used 4K 60 fps cameras.


Find the determinant of a symmetric matrix

How can we find the determinant of the following matrix?  $$A = \begin{pmatrix} x_1y_1 & x_1y_2 & x_1y_3 & \cdots & x_1y_{n-1} & x_1y_n \\  x_1y_2 & x_2y_2 & x_2y_3 & \cdots & x_2y_{n-1} & x_2y_n \\  x_1y_3 & x_2y_3 & x_3y_3 & \cdots & x_3y_{n-1} & x_3y_n \\  \vdots &  \vdots &  \vdots &  \ddots &  \vdots &  \vdots \\ x_1y_{n-1} & x_2y_{n-1} & x_3y_{n-1} & \cdots & x_{n-1}y_{n-1} & x_{n-1}y_n \\  x_1y_n & x_2y_n & x_3y_n & \cdots & x_{n-1}y_n & x_ny_n \end{pmatrix}$$  That is, the entry of $A$ is $a_{ij}=x_iy_j$ for $i\leq j$; and $a_{ij}=a_{ji}$ for $i>j$.  I do not have anything new. And I find also it is difficult to find its eigenvalues.


Just wanted some feed back on the following proof   "if $a$ divides $b$ and $b$ divides $c$ then $a$ divides $c$"  I came up with this:  If $a|b$ then there exist some $x$ that $a * x = b$ and if $b|c$ there exist some integer $y$ that $b * y =c$ therefore if $a|c=z$ and $z=xy$ then $(a|b)(b|c)=a|c )$.  Please let me know if I got this correct and I also wanted to know if there are more than one way to prove this statement, Thank you.


what is the limit of $\displaystyle \lim_{x\to 0} \frac{x}{a}\cdot \lfloor{\frac{b}{x}\rfloor}$

find the limit of:      $\displaystyle\lim_{x\to 0} \frac{x}{a}\cdot  \lfloor{\frac{b}{x}\rfloor}$      $ a,b>0$   i know that: $\lfloor\frac{b}{x}\rfloor\le \frac{b}{x} + 1$; and  $\lfloor\frac{b}{x}\rfloor\ge \frac{b}{x} -1$  but i cant seem to combine those using the squeezing theorem (i belive the limit is $\frac{b}{a}$)


The set of limit points in a $T_1$ space is closed

Prove the set of limit points in a $T_1$ space is closed.  Definitions:  Limit Point: $x$ is a limit point of a set if every open set that contains $x$ contains at least one other point of the set that is not $x$. $T_1$-space: All pairs of disjoint points have neighborhoods not containing each others' points.  I wrote that all points in the set of all limit points are disjoint from the complement of the set of all limit points, so all the points in the complement of the set of all limit points have neighborhoods that are disjoint from all the neighborhoods of all the points in the set of all limit points, but this was marked incorrect. How should I go about proving this correctly?


How do Muggle Wars affect the magical world?

This came up to me while I was reading the question about Magical being using firearms in battle to raise their power (which I think I have a good answer for, but it's too long to fit in this question... and it would also be inappropriate).  Anyways, I was reading it and then the following thought came into my mind: If wizards decided to use guns on their battles (the ones agains Voldemort for instance), that would create that opening for much bigger battles than we see in the books (after all even a muggle can fire a gun, so lots of guns + the Imperio curse, and presto manifesto (is that racist? talking about wizards and all) you have yourself an army). Those kinds of battles, however, would most definitely not go unnoticed by the muggles - even though they wouldn't be able to link it to magic.  Well, that thought brought up my one and final question, which I bring forth to you guys. Is there any mention on how the Wizards and Witches viewed the two world wars (which had taken part by the time Harry got to Hogwarts, and which he had probably heard about in muggle school), and what was the Wizards' part in it? What about the cold war? Did the magical world even recognise the existence of weapons such as nukes, which could render all life on earth extinct?  EDIT  DVK has brought up an  regarding the connections between the Second World War and the wizarding world (more specifically, the wizard Grindelwald). Although it doesn't fully answer my question, it does help by showing that there was indeed some form of connection between the two world at the time.


Are the Pokémon that appear in the Pokémon GO app region specific when it comes to elemental pokemon? I live in Arizona and got a Magikarp in an egg and I do not know where to find any more whatsoever and I am not looking forward to getting 400 points to make it evolve when I can't even find one.


How can I copy the path of a file in Finder?

How can I copy the path to a folder or a file? The Info Dialog doesn't allow me to copy the information that stands there ...    Is there an easy way to do this?


Are all limits solvable without L'Hôpital Rule or Series Expansion

Is it always possible to find the limit of a function without using  or ?  For example,   $$\lim_{x\to0}\frac{\tan x-x}{x^3}$$  $$\lim_{x\to0}\frac{\sin x-x}{x^3}$$  $$\lim_{x\to0}\frac{\ln(1+x)-x}{x^2}$$  $$\lim_{x\to0}\frac{e^x-x-1}{x^2}$$  $$\lim_{x\to0}\frac{\sin^{-1}x-x}{x^3}$$  $$\lim_{x\to0}\frac{\tan^{-1}x-x}{x^3}$$


Scheduler start time not available in AynchApexJob

From the AsyncApexjob object, I am unable to get the scheduled start time of a job. Is there a way to get the start time of a apex job.


As an American, I am used to driving on the right, and that the left lane on a major highway is supposed to be the "fast lane"...  If I attempt to drive in the UK, is the right lane the "fast lane" on major highways?


Will moving my debt from one credit card to another affect my credit score?

I have a card that is 50% used with 7% interest. The max credit limit on the card is $10,000, and I used $5000. I have another card that is $14,000 and I have $2900 used, but the interest is 14.9%. I want to move the $2900 card to the other card that has a lower interest rate (7%). This will bring the balance close to the max, but the idea is to focus on this one card and bring the balance down as quickly as possible. is this a wise choice? I am looking to purchase a house in 6 months so I thought that this might be enough time to pay it off and keep my score up. My scores are currently in the low 700s.


preg_replace only replaces first occurrence then skips to next line

Got a problem where preg_replace only replaces the first match it finds then jumps to the next line and skips the remaining parts on the same line that I also want to be replaced.  What I do is that I read a CSS file that sometimes have multiple "url(media/pic.gif)" on a row and replace "media/pic.gif" (the file is then saved as a copy with the replaced parts). The content of the CSS file is put into the variable $resource_content:  $resource_content = preg_replace('#(url\((\'|")?)(.*)((\'|")?\))#i', '${1}'.url::base(FALSE).'${3}'.'${4}', $resource_content);   Does anyone know a solution for why it only replaces the first match per line?


Correct sequence of MSSQL Server updates

What is the correct sequence to follow when updating MSSQL Server to a new service pack?  For example, if I have an instance of MSSQL Server 2016 RTM and I wish to update to SP2, do I need to first update to SP1 and and any of the cumulative updates in between or is it only necessary to update to SP2?  If there were cumulative updates available for SP2, would I need to first update to SP2 before running the latest cumulative update or is it only necessary to run the latest cumulative update?


I've been playing around with the Matasano crypto challenges (cryptopals.com). I had a couple false-starts on the challenge that has you creating a program to calculate the key size of a XOR encrypted file using Hamming Distance of the bits (Index of Coincidence). After some head banging and pen and paper work on graph paper, I arrived at a working solution.  I've been playing around with my new toy script with different ciphertexts and key lengths and I noticed that for key sizes greater than 12 bytes, it works well (in my limited testing) and will accurately return the correct key size. For shorter key sizes, the most probable key length returned is a multiple of the correct key size. In fact the first few most probable key sizes are multiples of the correct key size and then the correct key size will appear further down in the results but with a higher probability ranking (based on Hamming Distance), than smaller, incorrect values.  Here's some examples that demonstrate what I'm talking about:  key = "eatoin shrdlu"  key.length  13  Let's XOR encrypt our plaintext with the key and get cipherText:  cipherText = XOR-Encrypt -String data -key key  cipherText (line breaks added) 21041a01001d003501010c090745151503021d000401060c4c31040f54240803491d1b191d4c14 070e011b491a4816482421223a2841161a0e4200070017441a140914114f060800050100101914 0941190e0a06491d0d52011f160411111c454e571b1152011a1017181b010c4e57120606174c01 0a41190e020b00161e171615550714134f1d0645531f1d161f01450e1a0a49014653091e084c01 0c0c114f061c00191d01104c14450301010a06001c0e520c1505004115010d4e571b090644181d 004135190c0047161a014404141304541b064e441c48050d181d45170103070b52120a1b080501 1c4110061a0d4c1c1b0716095b  Let's run this through the XOR brute forcer to see what it says about the key size:  XOR-Brutr -MaxKeySize 40 -String cipherText -Encoding base16 | Sort-Object AvgDist  KeySize          AvgDist -------          ------- 13               2.74660633484163 39               2.78461538461538 26               2.81730769230769 33               2.8989898989899 40               2.905 25               2.93 38               2.94210526315789 ...    Beautiful! The result correctly calculates that the key size is 13 bytes, but with smaller keys....  key = "eatoin shrdl"  key.length  12  cipherText = XOR-Encrypt -String data -key key  XOR-Brutr -MaxKeySize 40 -String cipherText -Encoding base16 | Sort-Object AvgDist  KeySize          AvgDist -------          ------- 24               2.58333333333333 36               2.66111111111111 38               2.85789473684211 40               2.915 19               2.95215311004785 29               2.97536945812808 22               3.00909090909091 16               3.02232142857143 23               3.03381642512077 18               3.03703703703704 37               3.03783783783784 14               3.05357142857143 30               3.05714285714286 32               3.0625 27               3.06481481481481 12               3.06578947368421 28               3.06632653061224 ...   Our top result is not 12, though 12 is the greatest common denominator of the top two results.  If we set the MaxKeySize to a higher value and use a 26 byte key:  key = "eatoin shrdluuldrhs niotae"  ciphertext = XOR-Encrypt -String data -key key  XOR-Brutr -MaxKeySize 104 -String CipherText -Encoding base16 | sort avgdist | select -First 10  KeySize          AvgDist -------          ------- 52               2.59615384615385 78               2.62179487179487 104              2.64423076923077 81               2.66666666666667 26               2.66826923076923 84               2.67857142857143 ...   Again, a multiple of the actual key rises to the top.  Question: Why does this pattern emerge? Why does the Hamming Distance favor multiples of the actual key size? Should my script determine the gcd of the first few results and weight the gcd more heavily and return it as the probable key?


Zeros of the equation $e^z-z$ in the complex plane

Does $e^z -z$ have any zeros?   By plotting the functions $e^z$ and $z$ in the real line, I have seen that this equation does not have any zeros in the real line. Can the same thing be said for the complex plane? Being an entire function, I know that it assumes every finite complex number except atmost one. But what about the zero? Please help.


How can I remove all transient objects from multiple photos, leaving only the background?

I have multiple images of (let's say) a busy street. All taken with the exact same angle, and the people are moving around.   It stands to reason that if I could compare all images and get only "the part that is common to all images", I would have an image of an empty street.   Any thoughts on how this could be achieved?


This is similar to:  and , but is slightly different. The other questions are asking more of a why question, not a please do this question. I am asking for a specific implementation of Markdown tables. I found  on making tables in Markdown using  or . The code to make a table looks like this:  | Left align | Right align | Center align | |:-----------|------------:|:------------:| | This       |        This |     This     | | column     |      column |    column    | | will       |        will |     will     | | be         |          be |      be      | | left       |       right |    center    | | aligned    |     aligned |   aligned    |   And the result is:   This is much different than , which says that Jeff doesn't want the <tr><td> tags allowed on the SE sites. This request has a specific feature request, as opposed to the other questions which don't really have a decisive yes/no answer.  Here are some specific posts that need this type of support:


I have $P(x)$ a polynomial with degree $n$ ,$P(x) \ge 0$ for all $x \in$ real.  I have to prove that:     $f(x)=P(x)+P'(x)+P"(x)+......+P^{n}(x) \ge 0$ for all $x$.   I tried different methods to solve it but I got stuck.Any suggestion or advice is welcomed.


Epsilon delta proof for $\lim_\limits{x\to a} \sqrt{x} = \sqrt{a}$ where $a>0$

$f(x) = \sqrt{x}$. For right limit, $x-a > 0$. Let $x-a < \delta$ then $(\sqrt{x}-\sqrt{a}) \lt \frac{\delta}{\sqrt{x}+\sqrt{a}}$. Then chose we must choose $\epsilon $ so that $\epsilon > \frac{\delta}{\sqrt{x}+\sqrt{a}}$. Is this correct? How would I conclude the proof?  Edit - Follow up  From answers, I try a proof for the same limit but this time Left side:  For left side limit, $x-a < 0$ so $a-x > 0$. Let $a-x < \delta$ then $\sqrt{a}-\sqrt{x} \lt \frac{\delta}{\sqrt{a}+\sqrt{x}} \lt \frac{\delta}{\sqrt{a}}$.   So let me begin the proof by saying to choose $\delta = \epsilon \sqrt a$ then $a-x \lt \delta $ so $(\sqrt a - \sqrt x )(\sqrt a + \sqrt x) \lt \epsilon \sqrt a$ so $\sqrt a - \sqrt x \lt \epsilon$


I am trying to understand the Georgi chapter of tensor methods in $SU(3)$ representations, and I don't know how to resolve the tensor product of 2 matrices in a 2 heavy quark + 2 light antiquark system. Namely:  Let the tetraquark system be:           $QQ\bar q\bar{q}$  So, those $Q$ heavy quarks interact and can be understood in the $3\bigotimes 3$ representations for $SU(3)$, and $\bar q\bar q$ can be understood as the $\bar 3\bigotimes\bar 3=3\bigoplus\bar 6$ representations for $SU(3)$.  The interaction diagram for the $Q$ heavy quarks is shown in the following scheme, which is an analogy to the Feynman Diagram where a gluon is understood to be exchanged between upper and lower arrows:  $i'\xrightarrow{(T_{a})^{i'}_{i}}i ,  {}^iQ$  $j'\xrightarrow{(T_{a})^{j'}_{j}}j ,  {}^jQ$  So, as usuall we consider the elements of $3$ representation as $u^i$, and therefore the elements of $\bar 3$ representation as $v_{j}$.  I must understand how does the following expression transform:  $(T_{a})^{i'}_{i}(T_{a})^{j'}_{j}\cdot(1/2)\cdot (w^iv^j+w^jv^i)=\Xi\cdot(1/2)\cdot(w^{i'}v^{j'}+w^{j'}v^{i'})$  In other words, how can one give the correct value of $\Xi$?  Note1: $T_a$ is understood to be the $a-ith$ generator of the associated Lie Algebra, which come from the definition of the Gell-Mann Matrices.  $(T_{a})^{i}_{j}\propto(\lambda)_{ij}$, in matrix notation.  Note2: I understand the Young Tableaux and they are not intended to be used here, so please don't try to explain this situation through the tables.   Also requesting information about how to understand the tensor products in these cases, since I have been checking many sources but the definitions seem not clear enough.


We saw Charles Xavier getting completely annihilated by Jean in the movie "X Men: The Last Stand". But, in the last movie in the series, "X Men: The Days of Future Past", we see Xavier alive. While there's a possible explanation of his existence in the changed parallel reality we see in the last, I cannot understand how he was alive in the first reality.  If anyone can shed light on this matter, it'll be greatly appreciated. Thanks. 😊


All derivations are directional derivatives

Let $X : C^{\infty}(\mathbb{R}^n) \rightarrow \mathbb{R}$ be a derivation, so i.e. linear and satisfying the Leibniz Rule  $$X(fg)=X(f) \cdot  g(a)+X(g) \cdot f(a)$$ for some fixed $a \in \mathbb{R}^n.$ Then I would like to see that $X = \sum_{i=1}^{n} a_i \frac{\partial}{\partial x_i}|_a.$ So I want to see that $X$ is essentially a directional derivative.


Is it too late to get the last updates for XP?

Obviously there won't be any more updates for XP, since they stopped supporting it as of today. However I still have a couple of XP machines around that I don't use much, and they haven't gotten the latest updates that were available. Did they shut off those servers or can you still get the older updates?


Where did newtonian size setting go in 2.79a

I am sure that beside Mass there used to be a particle size and size random setting here in previous versions of blender, but on 2.79a, I can't seem to find it?   Did I accidentally change a setting somewhere that turned it off  or did they remove it?    I know that I can use the Normal setting under velocity to control the size, but I am not sure how I can make the size random without randomizing the rotation also.


1607 writ by Edward Coke - Relative pronouns?

(Sir Edward) Coke further noted that   legal disputes about such matters as inheritance of goods:           are not to be decided by natural reason but by the artificial reason and judgment     of law, which law is an art which requires long study and experience, before that     a man can attain to the cognisance of it: that the law was the golden metwand     and measure to try the causes of the subjects; and which protected his majesty in     safety and peace. . . .      I know that this was written in 1607, but:    How would you determine the purpose of which? It doesn't sound like the modern relative pronoun; "which is an art which" sounds curious. This refers to .  I think that is optional, but is it truly? Why or why not?   This doesn't duplicate; the linked question doesn't answer question 2.   Source: P13, How the Law Works, Gary Slapper


Finding the closed form solution of a third order recurrence relation with constant coefficients

How would you solve for the closed form solution of a(n) given the general form of the third order linear homogenous recurrence relation with real constant coefficients.  $a_n=Pa_{n-1}+Qa_{n−2}+Ra_{n−3}$  with the initial terms of a_1, a_2, and a_3  given that the roots of the characteristic equations have  1)two repeated roots and a real root  2)three repeated roots  (can you give answers for both cases please)  When I search the web I get these results  1)$a_n = nAx_1^n + Bx_1^n + Cx_2^n$,for the case when there are two repeated roots  and  2)$a_n = n^2Ax^n + nBx^n + Cx^n$, for the case when there are three repeated roots  Can anyone help derive the closed form of each case in order to get such results?  Please help  I'm new to the system so i didn't quite know how to get the symbols right (sorry) if you're uncertain about anything please ask


Deserializing a string from JSON to DateTime in Apex yields "Invalid format" error

I have a string as,  field name : start Date: 2016-11-14 08:00 AM ( string type)  how to convert this to Date time. I tried Date.parseDate and below option also.  String val = recruiters[j].Start_Time_Formula__c;                              system.debug('val ::'+ val);                             DateTime date1 = (DateTime)Json.deserialize('"'+val+'"', DateTime.class);                             system.debug('date1 ::' + date1);   but I am getting error as,     System.JSONException: Invalid format: "2016-11-14 08:00 AM" is malformed at " 08:00 AM": (System Code)   I referred the below link and got with the above error.    any help ?


How to explain the force applied on this object?

Sorry for posting such a simple problem but I'm having trouble understanding this concept.  In the picture below, we have a force, $ \vec F_{app}$ acting on two objects, A and B.  Mass of block A: $ M_a = 4kg $  Mass of block B: $ M_b = 6kg$  The acceleration of the two blocks can be found using F=ma  $$ 20N = 10kg * a $$ $$ a = 2m/s^2 $$  If we find the force Fba on block B from block A we get:  $$ \vec F_{ba} = 6kg * 2m/s^2 $$ $$ \vec F_{ba} = 12N $$  What I am confused about here is why don't we say that the total force $ \vec F_{app} $ applied onto block A is also applied to block B (20N). Is the force somehow distributed into the blocks?


Suppose that $V$ and $W$ are vector spaces. Denote $V'$ as the dual space of $V$.  Let $T \in \mathcal{L}(V,W)$. Denote the dual map of $T$ by $T' \in \mathcal{L}(W',V')$  such that  $$ T'(\phi) = \phi \circ T $$  and if $U$ is a subset of $V$, then $U^0$ is its annihilator.  If $V$ and $W$ are finite dimensional, then  $$ \text{range } T' = (\ker T)^0$$  Howerver, I do not know if this is still true if one of the vector spaces is infinite dimensional. In the Sheldon Axler's Linear Algebra Done Right (3rd ed.), he proves that $\text{range } T' \subset (\ker T)^0$ without the hypothesis of their being finite dimensional. However, he uses this hypotheses to prove the inclusion in the other direction. So my question is: does the equality still holds if one of the vector spaces is infinite dimensional? If does not, could you show a counterexample.  Just consider during the explanation that my level of linear algebra is roughly that of the book Linear Algebra Done Right. So if the explanation requires more advanced knowledge, just explain it briefly, just to give me some feeling.  Edit:  $V'$ is the algebraic dual:  $$V' = \mathcal{L}(V,\mathbb{F}) $$  where $\mathbb{F}$ is the field, that is, $V$ is over the field $\mathbb{F}$.


Prevent Windows 10 from activating with Win 8.1 embedded BIOS key?

Let's say I have one of those Windows 8.1 Pro PCs that have the product key embedded in the BIOS. When you install Windows 10 to this, it will activate using that Windows 8.1 BIOS key.   However let's say I had a reason to use my own genuine Windows 10 Home (not pro) product key. I can go to Settings > Activation > Change Product Key and use the Win 10 key and it will say activation was successful.   However, running this wmic path softwarelicensingservice get OA3xOriginalProductKey shows the original Win 8.1 Pro embedded BIOS key even after a reboot. Also the System window shows the product key ending in -AAOEM which from my understanding means it is using the OEM embedded key.  I have tried completely reinstalling using the Win 10 ISO and their media creation tool. Windows 10 Home gets successfully installed and activates successfully, however always seemingly with the embedded BIOS product key and not the one I provided. However this may be just a misunderstanding on my part and I"m not 100% understanding that perhaps this is still being activated with my product key, but I can't see how I can tell. The "version" is successfully dowgraded from 8.1 PRO to 10 HOME by using the PID.txt method in the installation media.  Any ideas?  EDIT: This is unlike the suggested Possible Duplicate as in that thread, someone is trying to upgrade their overall edition, not downgrade. They are successfully activating but not with a new product key as I am trying to do.


How often are the top users in a tag calculated?

I've just been going through and unifying  with  because though the first existed before and the second didn't, the second is much closer to the formal name of the thing to which it refers to. So far, so ho hum.  But now that I've adjusted all the questions so that they're tagged with the improved tag, I can't nominate any synonyms for it. OK, I'm not sure if I have 5 upvotes in the tag (I might do) but when I look at the list of top users in it, it's empty! “A-hah! Needs a recalc!” I think.  So, how often are such recalculations performed? How long do I have to wait before I can see whether it is reasonable for me to try to propose a tag synonym?


How can I create the decision tree below?

Can someone help me with this figure? I need to add it to a Latex document and I don't know how to use function properly.


I would like to play a video in a dialog window, but it doesn't work. The video is instead of the "raw" directory. I don't know where I'm wrong. Can you help me Please? There is the code  ImageButton video_player = (ImageButton) findViewById(R.id.img_btt_on_ear_watch);         video_player.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View view) {                 final Dialog dialog = new Dialog(context);                 dialog.setContentView(R.layout.layout_video_player);                  String filePlace = "android.resource://" + getPackageName() + "/" + R.raw.grado_video_cuffie_making;                 VideoView videoV = (VideoView) findViewById(R.id.vv_video_player);                 Uri videoURI = Uri.parse((String) filePlace);                 videoV.setVideoURI(videoURI); //this is the 128 raw                 videoV.setMediaController(new MediaController(context));                 videoV.start();                  ImageButton dialogButton = (ImageButton) dialog.findViewById(R.id.img_btt_vv_close);                 // if button is clicked, close the custom dialog                 dialogButton.setOnClickListener(new View.OnClickListener() {                     @Override                     public void onClick(View v) {                         dialog.dismiss();                     }                 });                  dialog.show();              }         });   There is the Logcat  11-15 10:40:50.666 3893-3893/com.huawei.headphones.huaweimusic E/AndroidRuntime: FATAL EXCEPTION: main                                                                                Process: com.huawei.headphones.huaweimusic, PID: 3893                                                                                java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.VideoView.setVideoURI(android.net.Uri)' on a null object reference                                                                                at com.huawei.headphones.huaweimusic.Activity_Cuffia1$1.onClick(Activity_Cuffia1.java:128)                                                                                at android.view.View.performClick(View.java:5610)                                                                                at android.view.View$PerformClick.run(View.java:22265)                                                                                at android.os.Handler.handleCallback(Handler.java:751)                                                                                at android.os.Handler.dispatchMessage(Handler.java:95)                                                                                at android.os.Looper.loop(Looper.java:154)                                                                                at android.app.ActivityThread.main(ActivityThread.java:6077)                                                                                at java.lang.reflect.Method.invoke(Native Method)                                                                                at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)                                                                                at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)


How to find all file sizes under Windows folder?

My Windows folder size is nearly 500 GB and I can't find which folder or file size is huge. Is there any way to find this huge file?


Manuscript submitted to Crelle's journal without acknowledgement

I submitted a manuscript to Crelle's journal about a month ago but never received a confirmation email from the editor whom I emailed the manuscript. I sent him/her another email asking about the status of paper and never heard back. I was wondering if that is a common and that is how it works with them.


I recently bought an external monitor which I use in Portrait mode attached to my laptop.  With quite some regularity I have to connect/disconnect it monitor (I work at home and often need to move to another room).  But this means that every time that I have to connect/disconnect it, I have to reset it with the display manager.  And that means doing quite a number of clicks and wait a few annoying seconds between each click.: first to activate the external monitor, then to rotate it 90 degrees, and then to place it on the left of the monitor (or to turn the laptop off).    Is there a way that I can expedite this, either by having the display manager remember some of my configurations or by writing a command script that I can just invoke and which will set up up my monitor in one single command/click?    I am using Xubuntu, so please let me know if this response is exclusive to this distribution (I suspect that it is not).  Thanks in advance.  Santiago.


Background Images are not showing up in the other views other than the camera view. It will show in the camera view but not in the other orthographic views. I have tried switching the set view that the image is visible in and increasing opacity to 1.0. I am in orthographic view when I am attempting this.   Here are the specs for my computer that I am aware of:    Blender Version: 2.78  Image format: jpeg  Graphics Driver: NVIDIA   OS: Windows 8.1   Edit: Here is an image of the setup. Nothing is changed except for the preset view (using left in this case).


Text mode acts like Enter key is held down

I recently ran updates on Xubuntu 18.04. Now if I go to a text-mode TTY, here's what happens:   Type anything as a username, just can't be empty. Press Enter. It behaves as if Enter is held down, immediately failing logon (as password is empty). After 5 failures, it clears the screen and no longer acts as if Enter is held down.   If I run physlock it just immediately acts as if Enter is held and fails infinitely.  Kernel version 4.15.0-43 works fine, but 4.15.0-44 and 4.15.0-45 are broken. The recovery root shell is unaffected, even when I run login from within it.


What data analysis is better? or fit for my data?  I've used Likert scale for my questionnaire (1-5) and I have 387 respondents.  Wilcoxon Rank Test or T-Test?


I have Ubuntu 14 installed and it dual boots with Windows 10. I want to extend the size of the Ubuntu partition.   I followed this article:   But when I swapoff my linux-swap, it says "Please unmount any logical partitions having a number higher than 5"  How do I resize now?   Here is the image:     I have 15GB and 4.5GB unallocated. How do I extend my current Ubuntu partition?


Is bootstrapping standard errors and confidence intervals appropriate in regressions where homoscedasticity assumption is violated?

If in standard OLS regressions two assumptions are violated (normal distribution of errors, homoscedasticity), is bootstrapping standard errors and confidence intervals an appropriate alternative to arrive at meaningful results with respect to the significance of regressor coefficients?  Do significance tests with bootstrapped standard errors and confidence intervals still "work" with heteroscedasticity?  If yes, what would be applicable confidence intervals that can be used in this scenario (percentile, BC, BCA)?  Finally, if bootstrapping is appropriate in this scenario, what would be the relevant literature that needs to be read and cited to arrive at this conclusion? Any hint would be greatly appreciated!


Why direction of Ampere's Law follows right hand rule?


invoke synchronized static method,then can other static methods be accessed?

I have an question about synchronized static methods. If i invoke a synchronized static method, does it mean i lock this class and other method (including static or no static) can not be accessed before the synchronized static method end?  When A synchronized static method is locking class object, why the other static method can be invoked at the same time?  class Y {     static synchronized void staticSleep() {         System.out.println("Start static sleep");         try {             Thread.sleep(2000);         } catch (InterruptedException e) {         }         System.out.println("End static sleep");     }     static void staticSleepNoSyn() {         System.out.println("Start static NoSyn sleep");         try {             Thread.sleep(2000);         } catch (InterruptedException e) {         }         System.out.println("End static NoSyn sleep");     } }   public class X {     public static void main(String[] args) {         for (int i = 0; i < 2; ++i) {             new Thread(new Runnable() {                  public void run() {                     Y.staticSleep();                 }             }).start();         }          for (int i = 0; i < 10; ++i) {             new Thread(new Runnable() {                  public void run() {                     Y.staticSleepNoSyn();                 }             }).start();         }     } }   the output:     Start static sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   Start static NoSyn sleep   End static sleep   Start static sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static NoSyn sleep   End static sleep


Why does the characteristic of a finite field always have to be prime?

I know little about group theory, and the concept of a field characteristic is new to me. Although there are some posts on this website that explain it very well.  "In layman's terms, it's the amount of times we can keep adding 1 to itself without looping back to 0. The characteristic being $p$ means that $\underbrace{1+1+\dots+1}_p=0$."  I think I can get my head around the idea, but there is still something I don't understand.    "We can see quickly using a zero divisor argument that the characteristic of any field with positive characteristic must be prime."  Why is it that it has to be prime? Why can't it be something else?


90s Science fiction children's book with glass grass

I read this science fiction story in 5th grade that had a female main character and she was on this alternate planet and the grass was like glass. Does that ring any bells for anyone. Would have been mid 90s when I read it.


Proving that the sample mean of a random sample drawn from the standard Cauchy distribution is also standard Cauchy distributed

Let X1, X2 be a random sample of size 2, drawn from the standard Cauchy distribution. How can you prove that the sample mean is also Cauchy distributed? I know how to do it by using the characteristic function, but we are asked to do it by using the following integral identity: $1/\pi * \int_{-\infty}^{\infty} arctan(2x - y) / (1 + y^2) dy = arctan(x)$ I know that $f(x)= 1/(\pi (1 + y^2))$ and $F(x) = arctan(x)/\pi + 0.5$. From there on I’m really stuck. Any help would be greatly appreciated, thank you in advance! A follow up question is proof by induction that the sample mean of a random sample of size n also has a (standard) Cauchy distribution. The first step of the induction proof is showing that it's true for, for example, n=2. I don't know how to continue from there on.


I understand the definition of eigenvalues and eigenvectors. Eigenvectors just stretch when applied by a linear transformation (a matrix). So far so good.  I am surprised by the amount of times they are coming up in my studies of matrix algebra and optimization. Yet, nowhere I find an intuitive explanation of why they are so important and why they keep coming up in so many problems?  Are there any eigenvalue theorems or something (like the normal distribution's explanation using the central limit theorem justifies its omnipresence) that explain why they are so important, what do they tell us?  EDIT: Please explain in terms of matrices, what do eigen values tell us about, say Hessian for example. I am trying to understand what do eigen vectors tell us about optimization problems in high dimensional spaces, Shapes of the curves, number of saddle points.  EDIT: The question in the duplicate link tallks about the connection between systems of differential equations and eigenvectors. I am trying for optimization in high dimensional spaces, Hessian based explanation.


Infinite sum of a series $\frac{N}{100} .( \frac{99}{100})^{(N-1)}$

What is the sum of the following series?  $$\sum_{N=1}^\infty\frac{N}{100} \cdot\left(\frac{99}{100}\right)^{N-1}$$?  This looks like a geometric series but I think the infinite sum formula wouldn't work here as there's an $\frac{N}{100}$ in front of the series?   I think the series converges to $100$, but I'm not sure how to get there


let $f(x,y)= e^{-\frac{1}{x^2+y^2}}$ when $(x,y)\neq (0,0)$ and $f(0,0)=0$.  Then   (1) $f$ is not continuous at $(0,0)$.  (2) $f$ is continuous but the first order partial derivative does not exists   (3) $f$ is continuous at $(0,0)$ , first order partial derivative exists but not differentiable   (4) differentiable .  I think only (2) is correct .  Reasoning :  set $r=x \cos \theta ,y=r \sin \theta $. Then as $(x,y)\to (0,0$) we have $r\to 0$ . so $ \lim_{r\to 0} f=\lim _{r\to} e^{-\frac{1}{r^2}}=0 . $ but  $\lim\frac{f(h,0)-f(0,0)=}{h}=\lim_{h\to 0}\frac{e^{-\frac{1}{h^2}}}{h}=\lim_{h\to 0}\frac{1}{he^{\frac{1}{h^2}}}$ does not exists as it becomes unbounded .   So the first order prtial derivatives does not exists .Hence it is not differentiable .  is my solution correct ?


I want to print the following path D:\\hl_sv in the PDF document but I am facing problem that the backslash are not being displayed. How can escape them to write them in the pdf document.  tex code:  \documentclass[paper=a4, fontsize=11pt]{scrartcl}   %  \usepackage[ngerman, english]{babel} \usepackage[protrusion=true,expansion=true]{microtype}    \renewcommand{\baselinestretch}{1.5} \usepackage[backend=bibtex]{biblatex}  \addbibresource{references.bib}  \begin{document}  \begin{itemize}  \item[1.] Currently, the parser parses PDF files in this path \textbf{D:\\hl\_sv} which needs to be changed to the saved timetable files path. \end{itemize}  \end{document}


Glitchy colors in minecraft that have nothing to do with graphics card

Now this doesn't have anything to do with my graphics card. This only happens in Minecraft. I use Windows 7, the problem starts and stops randomly. It only affects in game, not the menu, only the part where you actually run around.   I played around with the options, but nothing seemed to fix it. The colors turn from creepily shaded red and blue grey, and colors that look like an acid trip. The shading freaks out and teleports to different sides of blocks in a pattern that looks almost like the biggest QR code in the universe. If I dig down one block, its red and blue. This isn't caused by the 3D anaglyph; I always have it off.


Avoids "to speak", or "speaking", to me?

Another baffling change/that I notice in him now-a-days/is that he avoids to speak to me.   In this sentence the error is said to be "to speak" is wrong and "speaking" will be used. I am not sure with which grammatical rule speaking should come.


Changing decimal separator in existing columns in LibreOffice Calc

In LibreOffice Calc, if I have a column with a lot of numbers in this format 8,1 (comma), how  can I transfer all these numbers to the format 8.1 (dot)?  When I say "a lot" I mean thousands of numbers, so it is just impossible to rewrite it again in the right format.


Algorithm for finding similar images using an index

There are some surprisingly good image compare tools which find similar image even if it's not exactly the same (eg. change in size, wallpaper, brightness/contrast). I have some example applications here:   Unique Filer 1.4 (shareware):  Fast Duplicate File Finder (Freeware):  Visual similarity duplicate image finder (payware):  Duplicate Checker (payware):    I only tried the first one, but all of them are developed for Windows and are not open source. Unique Filer was released in 2000 and the homepage seems to have disappeared. It was surprisingly fast (even on computers from that year) because it used an index and comparing some 10000 images using the index needed only some few seconds (and updating the index was a scalable process).  Since this algorithm in a very effective form already exists for at least 15 years, I assume it is well-documented and possibly already implemented as an open source library. Does anyone knows more about which algorithm or image detection theory was used to implement this applications? Maybe there is even a open source implementation of it available?  I already checked the question  but all of it's answers solve the problem by comparing one image to another. For 1000+ images this will result in 1000^2 comparing operations which is just not what I'm looking for.


I was able to create a bootable USB drive with Ubuntu 18.10 but when I try to use as Live option, I don't know the logon and password and see no way to create a new one. Can you help?


Where can I ask questions about beauty tips on SE?

Is there a Stack Exchange site where users can ask questions about skin care, cosmetics and beauty tips for both sexes?


What would be the max current an 0805 0Ohm 5% resistor can handle (5V-24V) ?  Thanks for your answer.


I've noticed that many circuits use 22pF capacitors. For instance, the Arduino uses them to ground the oscillator pins of its AtMega328. Many tutorials call for  for simple circuits.  Why is specifically 22 pF so common? Why not 20 or 25, which are arguably "rounder" numbers?


How to stop "tail -f" within a running script?

How can you stop a tail -f command after seeing a specific string/word?  I'm trying to follow an expanding log and stop the tail after finding a specific word. Is there any kill command for that? I'm just starting with UNIX.


Given an itinerary receipt from a travel agent, how do I find out the fare conditions of the ticket?

For the first time in a long time, I traveled on a ticket that was purchased (in the US) at a travel agent. Our travel party got itinerary receipts, not e-tickets. At the end of the itinerary receipt, there was a brief description of fare restrictions; but there was no notice of terms incorporated by reference, as I'd always seen with my past e-tickets.   My understanding of Federal regulations is that whatever document you get that embodies the contract of carriage is supposed to have this notice of terms being incorporated by reference. I'm in a dispute now with the airline about fees, so this technicality is relevant.  Do itinerary receipts typically not have this notice? If so, what's the argument that airlines make to say that they are still complying with Federal regulations?


What is the difference between the number of cores and the number of logical processors?

I have been doing some image processing on my computer using .  Specifically, I am running a 5x5 median filter on imagery.  I can specify the number of processes that occur simultaneously within the Erdas batch command window.  I have been observing unusual behavior when I specify 16 simultaneous processes, which lead me to double check the number of processors on the machine.  I used the following command prompt command to assess the number of processors:  wmic cpu > cpu.txt   Which yielded (in part):  Number of Cores: 8  Number of Logical Processors: 16   How does the number of cores differ from the number of logical processors in the context of software like Erdas imagine where the user can specify the number of simultaneous processes?  I am trying to determine if I should be specifying 8 or 16 simultaneous processes to maximize efficiency.


I am using the new TikZ/PGF 3.0 pic feature.  I use them heavily, including using a pic inside another pic.  The problem is that Tikz sometimes cannot find the node names of nested pics.  I expect the following to work:  \documentclass{standalone} \usepackage{tikz} \usetikzlibrary{positioning} \begin{document} \begin{tikzpicture} \tikzset{complex/.pic={   \node(re) {re};   \node[right=0mm of re](im) {im}; }} \tikzset{su3v/.pic={   \path pic(c0) {complex};   \path pic[right=1mm of c0im](c1) {complex};   \path pic[right=1mm of c1im](c2) {complex}; }} \tikzset{spinor/.pic={   \path pic(v0) {su3v};   \path pic[below=2mm of v0c2re](v1) {su3v};   \path pic[below=2mm of v1c2re](v2) {su3v};   \path pic[below=2mm of v2c2re](v3) {su3v}; }}  \path pic {su3v};       % Works \path pic(name) {su3v}; % ! Package pgf Error: No shape named namec0im is known. \path pic {spinor};     % ! Package pgf Error: No shape named v0c1im is known. \end{tikzpicture} \end{document}   What is wrong here?


What is the best cut of beef to use for stews?

What cut of beef should I use for a beef stew?  I heard that you want a little bit of fat in the meat, but what part the animal is best to use?