One of my answers on Ask Ubuntu meta reached the lofty heights of 25 upvotes and the relevant badge was duly awarded. However, I seem to keep getting the notifications:    Note that only the notification was received in triplicate. The badge was only awarded once.
Not sure if someone else has already raised this - I've got eleven notifications that I've received a Caucus badge on English Language Learners. Perhaps one notification for each community that I'm a member of?  I am a member of the community, and did visit the election. Also, the badge hasn't been awarded more that once (so I think it's just the notification that's at fault).  Note that this seems to happen for other badges, it has been reported for: Caucus, Nice Answer, Enthusiast.
A non orientable closed surface cannot be embedded into $\mathbb{R}^3$ The $ l^{\infty} $-norm is equal to the limit of the $ l^{p} $-norms. Which wire is negative on this PC fan? I just got this PC fan and it has a 3 pin connector, I know the wire with the white stripe is positive but how can I find out which of the other two wires are negative?  If you can't see the photo, here is a link to it: 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 many named characters died in Avengers: Infinity War? How many named characters have died       and/or disintegrated      by the end of Avengers: Infinity War. It is difficult to speculate who died on         Xandar and the Asgardian ship.       So restrict it to on-screen deaths only. If I seem tired, can I say: "I haven't slept last night"? If not, why have I been told that we use present perfect for actions that have present effects? $ a+b+c+d=6 , a^2+b^2+c^2+d^2=12$ $\implies$ $ 36 \leq 4(a^3+b^3+c^3+d^3)-(a^4+b^4+c^4+d^4) \leq48 $ Let $a , b, c, d$ be real numbers such that $$ a+b+c+d=6 \\ a^2+b^2+c^2+d^2=12$$  How do we prove that $$ 36 \space \leq\space 4(a^3+b^3+c^3+d^3)-(a^4+b^4+c^4+d^4) \space\leq48\space$$ ? The currently proposed Gravitational wave detection apparatus consists of Michelson Interferometer which is supposed to measure distances of the order of $10^{-22}$m. But the wavelength of the light used is in the order of micrometers ($10^{-6}$m). How is this possible? The conventional way to measure distance is by counting the interference fringes. But for path difference smaller than wavelength of laser light this is not possible. How do I alter a language item link? How to use GROUP BY to concatenate strings in MySQL? How to perform a true GIS clip of polygons layer using a polygon layer in R? I would like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the clip function in ESRI's ArcMap. I've tried the over method in sp package but it doesn't seem to work for polys over polys.   One suggestion was to use the gIntersection in rgeos package as a clip using the following code:  #------------------------------------ library(rgeos) library(maptools)  #Read layers as SpatialPolygonsDataFrame (both the same Albers projection) Soils_poly = readShapePoly("Soils_polygons")  #Note - Has 400 polygons clipper_poly = readShapePoly("clipper_polygon")  #Note - Has 1 polygon  #Try gintersection as clip  Clipped_polys = gIntersection(Clipper_Tile_poly, Soils_poly)  #-----------------------------------   This takes 5 minutes to run (way too slow) and errors with this:     Error in RGEOSBinTopoFunc(spgeom1, spgeom2, byid, id, drop_not_poly, "rgeos_intersection") :      TopologyException: no outgoing dirEdge found at -721459.77681285271 2009506.5980877089   I also tried this code to check for overlap:  gIntersects(Clipper_Tile_poly, Soils_poly)   and the result was TRUE. clip function in ESRI ArcMap works fine for this data.   Anyone knows of an R function to properly do a clip on spatial polygons using spatial polygons? How can I change the page URL without refreshing the page? Collinearity diagnostics problematic only when the interaction term is included When I have equations, as in  \begin{equation} ... \end{equation}   Can I arbitrarily assign the numbers to the equations? Instead of the usual order (1), (2), (3), ..., I'd like something like (1), (2.1), (2.2), (2.3), (3.1), (3.2), (4), ... How will multiple GPUs improve Cycles' rendering performance? I have an NVIDIA Titan GPU and I'm able to add another card, but I wonder whether  Blender will benefit from more than one GPUs?  Should I do it as SLI or should I just do it as an added card? I just need some help in understanding how Blender will use either SLI or a second GPU.  Note that I only use Cycles. Principal $n$th root of a complex number This is really two questions.   Is there a definition of the principal $n$th root of a complex number? I can't find it anywhere. Presumably, the usual definition is $[r\exp(i\theta)]^{1/n} = r^{1/n}\exp(i\theta/n)$ for $\theta \in [0,2\pi)$, but I have yet to see this anywhere. Is this because it has bad properties? For instance, according to this definition is it true that for all complex $z$ it holds that $(z^{1/a})^b = (z^b)^{1/a}$? (PHP) Is handling a form submission on the same page more/less/equally good as handling on a separate page? Ran out of inodes - 100% Full I am using Ubuntu 16.04 on AWS EC2 instance which has been working fine until this problem.  My problem is that I've used 100% of available inodes, as I discovered with this command:  $ df -i Filesystem     Inodes  IUsed  IFree IUse% Mounted on udev           124464    360 124104    1% /dev tmpfs          126787    449 126338    1% /run /dev/xvda1     524288 522638   1650  100% / tmpfs          126787      1 126786    1% /dev/shm tmpfs          126787      5 126782    1% /run/lock tmpfs          126787     16 126771    1% /sys/fs/cgroup tmpfs          126793      4 126789    1% /run/user/1000   The main culprits I discovered:  $ find / -xdev -printf '%h\n' | sort | uniq -c | sort -k 1 -n    1155 /usr/src/linux-headers-4.4.0-62/include/linux    1155 /usr/src/linux-headers-4.4.0-65/include/linux    1155 /usr/src/linux-headers-4.4.0-66/include/linux    1155 /usr/src/linux-headers-4.4.0-70/include/linux    1155 /usr/src/linux-headers-4.4.0-71/include/linux    1155 /usr/src/linux-headers-4.4.0-72/include/linux    1155 /usr/src/linux-headers-4.4.0-75/include/linux    1155 /usr/src/linux-headers-4.4.0-78/include/linux    1155 /usr/src/linux-headers-4.4.0-79/include/linux    1155 /usr/src/linux-headers-4.4.0-81/include/linux    1155 /usr/src/linux-headers-4.4.0-83/include/linux    1155 /usr/src/linux-headers-4.4.0-87/include/linux    1155 /usr/src/linux-headers-4.4.0-89/include/linux    1155 /usr/src/linux-headers-4.4.0-91/include/linux    1155 /usr/src/linux-headers-4.4.0-92/include/linux    1514 /usr/src/linux-headers-4.4.0-62-generic/include/config    1516 /usr/src/linux-headers-4.4.0-65-generic/include/config    1516 /usr/src/linux-headers-4.4.0-66-generic/include/config    1516 /usr/src/linux-headers-4.4.0-70-generic/include/config    1516 /usr/src/linux-headers-4.4.0-71-generic/include/config    1516 /usr/src/linux-headers-4.4.0-72-generic/include/config    1516 /usr/src/linux-headers-4.4.0-75-generic/include/config    1517 /usr/src/linux-headers-4.4.0-78-generic/include/config    1517 /usr/src/linux-headers-4.4.0-79-generic/include/config    1517 /usr/src/linux-headers-4.4.0-81-generic/include/config    1517 /usr/src/linux-headers-4.4.0-83-generic/include/config    1517 /usr/src/linux-headers-4.4.0-87-generic/include/config    1517 /usr/src/linux-headers-4.4.0-89-generic/include/config    1517 /usr/src/linux-headers-4.4.0-91-generic/include/config    1517 /usr/src/linux-headers-4.4.0-92-generic/include/config    1517 /usr/src/linux-headers-4.4.0-93-generic/include/config   Is it safe to delete these files, and if yes could you please tell me the exact command or commands to use on my PuTTY client? I am trying to make an explosion with Blender Mantaflow, but I do not see the following in the Properties view in the Physics Properties:  Color Mapping Smoke   I am using Blender 2.91. Can you help me solve the problem? What happens to objects that enter a Stargate from the destination side? We know that matter can only travel one way through a Stargate, ie. from the dialing gate to the destination. What happens to things that enter the wormhole from the destination side?   For example, if someone dials a gate that has tipped on its side (as in the SG-1 episode Hundred Days) and walks through, what happens when he reaches the other side and gravity causes him to immediately fall back into the gate?  Does the matter disappear, or does it pass through to the other side of the destination gate, as if the wormhole were not there?  Related: