I'm rendering some simple 3d shapes to an isometric perspective (orthographic cameras etc) using the Blender internal.  The render is lightning fast so I dragged out another 3d view so Blender is divided into two 3d Views, one on the left one on the right. (Properties editor is on the far right as usual).    When I press F12, initially Blender displayed the render result on the right hand view.  This was great as I could make small changes to the camera (on the left) and immediately see changes in the full render just by pressing F12 again.  However every so often when I press F12, Blender seems to randomly decide to put the render result in the left hand view and the right view now returns to the 3d View.      This a a real pain as I then have to re-open the tool and information panels and select the camera again etc.  It then also happens in reverse after a while (right now I'm rendering to the right window again).  I thought it may depend on which view I last selected an object in, but in my testing it seems to make no difference.    Does anyone know how I can lock the render result to a specific 3d view when there are multiple 3d views visible?
This has puzzled me for years: How does Blender decide the window where it will display the rendered image when I hit F12 to render?
Shutdown from terminal without entering password? I have desktop edition of Ubuntu.  I like the Terminal so that that I prefer to shutdown my computer with the shutdown command.  However when I type shutdown now it prompts me to enter my password.Is there any way I can shutdown my computer using this command without entering my password? Nonlinear regression model linear in some parameters In a set of  that I stumbled upon online, the author discusses a nonlinear regression model, which is linear in some parameters, like this $$ y = \theta_1 + \theta_2\exp \left( {\theta_3x} \right) + \varepsilon $$ and suggests to first perform a nonlinear regression to estimate $\theta_3$, and then use OLS to estimate the other two parameters. I am not very experienced in regression modeling, so please forgive me if I ask a very simple question, but I don't understand how you can do this consistently without also estimating the other 2 parameters? Apparently, there is some trick involved, which I don't understand...  Another question is what happens to the ability to do inferences based on parameter estimates to the complete model if you do the regression in two stages like that?  Many thanks! I'm trying to prove that for $p,q&gt;0$, we have $$\int_0^1t^{p-1}(1-t)^{q-1}\,dt=\frac{\Gamma(p)\Gamma(q)}{\Gamma(p+q)}.$$    The hint given suggests that we express $\Gamma(p)\Gamma(q)$ as a double integral, then do a change of variables, but I've been unable thus far to express it as a double integral.  Can anyone get me started or suggest an alternate approach?  Note: This wasn't actually given to me as the $\Gamma$ function, just as a function $f$ satisfying $$f(p)=\int_0^\infty e^{-t}t^{p-1}\,dt$$ for all $p&gt;0$, but I recognized that. This is in the context of an advanced calculus practice exam. sudo find / -name "*" | xargs grep -sn --color=auto "-j"   Above command returns below:  grep: invalid option -- 'j' Usage: grep [OPTION]... PATTERN [FILE]... Try `grep --help' for more information. ...   How do I search for string -j? "Overclocking" an AVR In AVR datasheets under the Electrical Characteristics section you will typically find a graph like this (this one is from the ATMega328):    I've seen designs that seem to "work" but operate outside the shaded envelope. Specifically, I've seen 3.3V (Arduino) designs that run the clock from an external 16MHz crystal. Clearly, this is out of spec. What are the practical negative consequences of running outside this envelope? Interpreting plot.lm() I had a question about interpreting the graphs generated by plot(lm) in R.  I was wondering if you guys could tell me how to interpret the scale-location and leverage-residual plots?  Any comments would be appreciated.  Assume basic knowledge of statistics, regression and econometrics. Computer doesn't boot up, shows PXE error and/or "operating system not found", "no bootable device", "insert boot media", or other similar error The following MWE compiles (for me)  \documentclass{article}  \usepackage{pgfplots} \pgfplotsset{compat=newest} \usetikzlibrary{external} \tikzexternalize[prefix=figures/externalized/]   \begin{document} \begin{figure}     \centering     \begin{tikzpicture}          \begin{axis}  %           \addplot3[surf,mesh/rows=129,mesh/cols=129,mesh/ordering=y varies] table[x=X,y=Y,z=psi] {figures/data/LidDrivenCavity/Lid_SPIKE_128x128_Re1000_psi.dat};              \addplot3[contour gnuplot,mesh/rows=129,mesh/cols=129,mesh/ordering=y varies] table[x=X,y=Y,z=psi] {figures/data/LidDrivenCavity/Lid_SPIKE_128x128_Re1000_psi.dat};          \end{axis}      \end{tikzpicture}     \caption{ciao} \end{figure} \end{document}   where the data file is . If I de-comment the first \addplot3 and comment the second one, then I get an error. The final part of the log file (the interesting one, I think) is  ===== 'mode=convert with system call': Invoking 'pdflatex -shell-escape -halt-o n-error -interaction=batchmode -jobname "figures/externalized/prova-figure0" "\ def\tikzexternalrealjob{prova}\input{prova}"' ======== \openout3 = `prova.auxlock'.  runsystem(pdflatex -shell-escape -halt-on-error -interaction=batchmode -jobname  "figures/externalized/prova-figure0" "\def\tikzexternalrealjob{prova}\input{pr ova}")...executed.  \openout3 = `prova.auxlock'.   ./prova.tex:22: Package tikz Error: Sorry, the system call 'pdflatex -shell-esc ape -halt-on-error -interaction=batchmode -jobname "figures/externalized/prova- figure0" "\def\tikzexternalrealjob{prova}\input{prova}"' did NOT result in a us able output file 'figures/externalized/prova-figure0' (expected one of .pdf:.jp g:.jpeg:.png:). Please verify that you have enabled system calls. For pdflatex,  this is 'pdflatex -shell-escape'. Sometimes it is also named 'write 18' or som ething like that. Or maybe the command simply failed? Error messages can be fou nd in 'figures/externalized/prova-figure0.log'. If you continue now, I'll try t o typeset the picture.  See the tikz package documentation for explanation. Type  H &lt;return&gt;  for immediate help.  ...                                                l.22    \end{tikzpicture}  ?  PGFPlots: reading {figures/data/LidDrivenCavity/Lid_SPIKE_128x128_Re1000_psi.da t} Runaway argument? {\pgfkeyssetvalue {/pgfplots/execute at begin plot visualization}{}\pgfkeyssetv alue \ETC. ./prova.tex:22: TeX capacity exceeded, sorry [main memory size=5000000]. &lt;argument&gt; ...5e-1],2Y7.753628e-3]}{2Y8.20894\ETC.  l.22    \end{tikzpicture}  If you really absolutely need more capacity, you can ask a wizard to enlarge me.   Here is how much of TeX's memory you used:  20761 strings out of 493054  547383 string characters out of 6134761  5000001 words of memory out of 5000000  23958 multiletter control sequences out of 15000+600000  3640 words of font info for 14 fonts, out of 8000000 for 9000  1141 hyphenation exceptions out of 8191  62i,4n,84p,728b,1519s stack positions out of 5000i,500n,10000p,200000b,80000s ./prova.tex:22:  ==&gt; Fatal error occurred, no output PDF file produced!   similar (or the same) error appears if externalization is not enabled/used.  My TeX distribution is TeX Live on Mac OS X 10.9.5 and I use TeXShop as editor.  Once I (partially) solved a  on Windows+MikTeX+TeXniccenter by modifying/adding options to the command executed when compile button is pressed. I say partially since I actually solved the problem for some data file. Then I experienced the same problem with larger datafile and/or different plots (I don't remember anymore) and didn't find a way out, no matter how much I extended the memory.  What should I do now? How do I join my partitions? Is there a measurable set $A$ such that $m(A \cap B) = \frac12 m(B)$ for every open set $B$? Algorithm to find the irreducible polynomial What algorithm can be used find an irreducible polynomial of degree $n$ over the field $GF(p)$ for prime $p$. The reason I ask is I want to make a program for finite field arithmetic, but creating a field $GF(p^k)$ requires finding a irreducible polynomial. (I'm mostly interested in $GF(2^k)$.) Alternating sum of binomial coefficients multiplied by (1/k+1) I'm trying to prove that  $$\sum_{k=0}^n {n \choose k} (-1)^k \frac{1}{k+1} = \frac{1}{n+1}$$  So far I've tried induction (which doesn't really work at all), using well known facts such as  $$\sum_{k=0}^n {n \choose k} (-1)^k = 0$$  and trying to apply identities like  $${n \choose k} = {n-1 \choose k-1} + {n-1 \choose k}$$  Would anyone be able to point me towards the right method? Should I be looking to apply an identity or is there a method I'm missing? Why is $1$ not a prime number? Why is $1$ not considered a prime number?  Or, why is the definition of prime numbers given for integers greater than $1$? On , this is my tag blacklist:        Note well that I have them set to hidden, because I would prefer not to see questions on this topic. Bridge players, don't take offence &mdash; I don't have problem with the game itself. I don't understand the game's mechanics, though, so I find questions about it incomprehensible, and I'd rather stick to just seeing questions I can understand.  I still see [bridge] questions galore on the Android app though. Could it be updated to pay attention to whether I have certain tags ignored and set to be hidden? divisibility of binomial coefficients by primes If $p$ is a prime number and $r = 1,2,3 \dots ,p -1$, how can I prove that the binomial coefficients $_nC_r(p,r)$ are divisible by $p$? By divisible I mean $_nC_r(p,r)/p$ leaves remainder $0$.  oivind How to make tr aware of non-ascii(unicode) characters? Beamer itemize not aligned when in blocks While making a poster, I've got two columns with blocks with itemize inside them. MWE:  \documentclass[final]{beamer} \mode&lt;presentation&gt;{}  \usepackage{times} \usepackage{amsmath,amssymb} \usepackage[english]{babel} \usepackage[latin1]{inputenc}  \begin{document} \begin{frame}[t]{}   %\leavevmode \begin{columns}[t, onlytextwidth] \begin{column}{.5\linewidth} \begin{block}{Contributions} \begin{itemize} \item First Item \item Second Item \end{itemize} \end{block} \end{column} \begin{column}{.5\linewidth} \begin{block}{Approach} \begin{itemize} \item First Item \item Second Item \end{itemize} \end{block} \end{column} \end{columns}  \end{frame} \end{document}   My local installation and ShareLaTeX would misalign the bullets(baselines added by me):   This problem seems similar to:        But this time it happens when itemize is inside the block. If one removes the blocks it works fine.  Am I missing something or does it look like a Beamer bug?  Thanks! I'm a LaTeX noob, sorry if I missed something stupid. Can't find boot-repair package for the newest version of Ubuntu After upgrading Ubuntu 13.10 to 14.04, grub failed to load Ubuntu and threw the error symbol 'grub_term_highlight_color' not found. I followed the solution offered in the  but this failed for me, throwing the error failed to get canonical path of /cow.   Now, I'm trying to install Boot-Repair to fix this problem on a live pen-drive, using these commands.   sudo add-apt-repository ppa:yannubuntu/boot-repair sudo apt-get update sudo apt-get install -y boot-repair &amp;&amp; (boot-repair &amp;)   But after adding and updating the repositories, it shows ppa:yannubuntu/boot-repair 404 Not Found error.  W: Failed to fetch http://ppa.launchpad.net/yannubuntu/boot-repair/ubuntu/dists/trusty/main/binary-amd64/Packages  404  Not Found   Is this problem solvable or is there an alternative PPA for Boot-Repair? It is given $23!=2585201xy38884976640000$. Now it is required to find the value of $x$ and $y$. I know I could find it by using divisibility rules and solving simultaneous equations. Is there any other way to solve it (without computing it by a calculator)? This question is just out of curiosity. When I change the stroke width of a rectangle the width and and height change also. How can I  prevent this from happening?