Is there anything I can do so that the PNG file name can have space and "ç"?  \documentclass[11pt,fleqn]{book}  \usepackage[top=3cm,bottom=3cm,left=3cm,right=3cm,headsep=10pt,a4paper]{geometry} \usepackage[portuguese]{babel} \usepackage{graphicx} \usepackage[]{titlesec} \usepackage[many]{tcolorbox} \usepackage{booktabs} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc}  \begin{document}      \section{Aba Esboço}  %Minitable     \tcbsidebyside[title=Aba esboço,     sidebyside adapt=left,     bicolor,colback=white,colbacklower=yellow!10,     fonttitle=\bfseries,center title,drop lifted shadow,     ]{%     \includegraphics[height=4cm]{Aba esboço.png}     %     }{%     Texto aqui.     } %  \end{document}     I only get some results using: aba_esboco.png    Result:    Aba esboço.png
I want to import graphics into my main input file using the macro \includegraphics. It does not work if the filename contains spaces.   also discusses this subject, but there is no solution there.  My compilation routine is latex->dvips->ps2pdf (because of PSTricks).
Suppose I am given a $2$x$2$ matrix $A=$ \begin{pmatrix} a &amp; b \\ c &amp; d \end{pmatrix}  And an initial vector $x_n$ = \begin{pmatrix} x_0 \\ y_0\end{pmatrix}.  Under repeated iteration $x_{n+1} = Ax_n$, we find that $x_{n+1}$ converges to a line in the direction of the $eigenvector$  of $A$ of the form $X$= $[u,mu]$ where $m$ is the slope of the line.  I know that this process somehow also involves the largest $eigenvalue, \lambda,$ of $A$, though I am unsure how it connects.  My question is: How does the largest eigenvalue connect to this repeated iteration, how do I find the slope of the line of convergence $m$, and what is meant by the "direction of the eigenvector"? Ignore folders/files when Directory.GetFiles() is denied access I am trying to display a list of all files found in the selected directory (and optionally any subdirectories). The problem I am having is that when the GetFiles() method comes across a folder that it cannot access, it throws an exception and the process stops.  How do I ignore this exception (and ignore the protected folder/file) and continue adding accessible files to the list?  try {     if (cbSubFolders.Checked == false)     {         string[] files = Directory.GetFiles(folderBrowserDialog1.SelectedPath);         foreach (string fileName in files)             ProcessFile(fileName);     }     else     {         string[] files = Directory.GetFiles(folderBrowserDialog1.SelectedPath, "*.*", SearchOption.AllDirectories);         foreach (string fileName in files)             ProcessFile(fileName);     }     lblNumberOfFilesDisplay.Enabled = true; } catch (UnauthorizedAccessException) { } finally {} Is there a better way than simply trying to open the file?  int exists(const char *fname) {     FILE *file;     if ((file = fopen(fname, "r")))     {         fclose(file);         return 1;     }     return 0; } I need to periodically run a command that ensures that some text files are kept in Linux mode. Unfortunately dos2unix always modifies the file, which would mess file's and folder's timestamps and cause unnecessary writes.   The script I write is in Bash, so  I'd prefer answers based on Bash. How can I maintain open ssh connection and use it from shell scripts? Currently i invoke the following:  $ ssh me@host.com my_cmd   This is slow and not easy to automate safely. I would like to establish ssh connection once and have some script that will forward my commands to host.com and print output.  Is that possible ?  Adding my machine to authorized_keys is not an option for me and it wouldn't solve slowness issue. How do I emit light from inside a object? How to install multiple versions of the same software? I manage phone systems for multiple clients. Each system uses the same administrator software, but it runs on different versions depending on what version of firmware is installed on the system controller.   The software is downloaded directly from the system controller so it's the right version. For example, if the controller runs on version 5.0.2, you have to run version 5.0.2 of the administrator software. You can't administrate a 5.0.2 controller with a later versions of administrator software.   Bottom line, you have to have the right version of software to log into the controller. The software is not executable on its own, you have to install it. So every time I want to log into a different controller, I have to reinstall the right software.   Any way to get around this?   I'm running Windows 7 Enterprise x86. Six simple tips to get Stack Overflow reputation fast Apply display settings to all user accounts? Please recommend undergraduate-level textbooks on electrodynamics which emphasize practical applications and real life examples. Please describe the book's level and contents and its intended audience in as much detail as possible.   Please provide both applications from everyday life for curious students as well as engineering applications from a physics perspective. I installed Ubuntu 14.04 onto my Acer Aspire E15. The PC has a 500 Gigabyte HDD.   During the installation it divided the HDD into separate partitions. However every time I turn on the PC it goes directly into Windows 8.1. It doesn't allow you the opportunity to select which OS you want to use.   Question 1: How do I set the PC so it will allow me to select the OS?  Question 2: And if #1 isn't possible. How to I remove Ubuntu from the PC and recover the partition for Windows Clicking on a spoiler tag to reveal the text shouldn't navigate you to another page This is an issue I noticed when reading . On multiple occasions I ended up inadvertently clicking a link that I could not see when I was just trying to reveal the spoiler text.         Can links be deactivated in spoilers until the text is revealed?  (Edit: this issue seems particularly to apply to those using touch screen devices with the "full site" theme) Can we really not tell if we are moving? It has been a while since I've thought about physics, however, I remember something about how if you are on a train with no windows that is going perfectly straight and is perfectly smooth, there is no experiment that you could perform to prove that you are in motion or at rest. So I have a couple of questions related to this.   Is this still held to be true? I was just wondering if anything in physics has come to light since I learned about this (about 10 years ago) that would allow an observer on the train to tell if they are moving. If this is true, why couldn't you accelerate a particle in different directions to a certain mass and measure how much energy it took to get it up to that mass. If you were moving in any direction, wouldn't you measure less energy in your direction of travel? Would having an outside observer affect the aforementioned experiment in any way? Moving an already-running process to Screen My office job routinely sees me connected to a Linux box via VNC.  Sometimes I start a remote job on the console, and realize later that it runs much longer than expected. (Should have started that one under Screen in the first place...)  I don't want to keep my workstation running overnight just to keep the VNC session open; I would like  to move that already-running remote job into a Screen session (on the remote box), so I can power down the workstation (and reconnect next morning).  How can this be done, if at all? \AtEveryBibitem{\clearfield{Title}} in beamer? In my beamer presentation, I want to cite the reference without title. So, I tried:  \documentclass{beamer} \usepackage[   backend=bibtex8,   defernumbers=true,   sorting=none,   firstinits=true,   uniquename=init,   uniquelist=false,   refsegment=section,   citestyle=numeric ]{biblatex} \addbibresource{mini.bib} \AtEveryBibitem{\clearfield{Title}} \begin{document} \section{Start} \begin{frame}   first cite\footfullcite{Julie2006}   %\printbibliography \end{frame} \section{2nd} \begin{frame}   Second cite\footfullcite{gyof} \end{frame} \end{document}   with the mini.bib :  @article{gyof,   Author={BLJ},   Title={Some Title},   Journal={joural1},   volume={15},   pages={1337},   Year={1985} } @article{Julie2006,   Author={JBS},   Title={Some Other Title},   Journal={journal2},   volume={74},   pages={144411},   Year={2006} }   with \AtEveryBibitem{\clearfield{Title}} I was expecting no title will be produced, but thats not the case:   Is there any incompatibility between clearfield and footfullcite? Or I am just missing something? Additive Roman Numeral 4 I am working on a diplomatic edition of a 15th century book and it numbers its folios using the standard roman numerals of the time.  I've been using the following to get the page/folio in my header:  \newcommand{\rectoverso}[1]{\ifthenelse{\isodd{#1}}{r}{v}} \newcommand{\folio}[1]{\the\numexpr (#1+1)/2\relax} \uppercase\expandafter{\romannumeral \value{\folio{\thepage}}}\rectoverso{\thepage}   This works great, but the problem is that the roman numeral sequence is off of what I need.  Instead of I, II, III, IIII, V, VI, VII, VIII, IX, X, I get the subtractive IV (somewhat understandably, given it's the far more common one in modern usage).  My source text only (and always) uses the additive 4 in the one's position: 24 is XXIIII, 34 is XXXIIII but 44 is XLIIII.  9 is universally rendered subtractively as IX or XC.  Is there a package that allows for some control over which numbers are done additively and which are subtractively, or would my best option be to write my own custom definition to account for the specific style used in my book? A simple regex search and replacement in php for minifying/compressing javascript? Considering the irreducible (by condition) polynomial $f=X^4-2aX^2+b\in\mathbb Q[X]$ and the field extension $K=\mathbb Q(\sqrt{a^2-b})$ of $\mathbb Q$, I want to show the following result:    For $[L:\mathbb Q]=4$ we have $\sqrt b\in K$ where $L$ is the splitting field of $f$.   My thoughts so far: The four roots of $f$ are $\pm\sqrt{a\pm\sqrt{a^2-b}}$. If $L$ is of degree $4$ it must be primitive since $f$ is irreducible, so $L=\mathbb Q\left(\sqrt{a+\sqrt{a^2-b}}\right)$. Then, by multiplying the two roots $\sqrt{a+\sqrt{a^{2}-b}}\cdot\sqrt{a-\sqrt{a^{2}-b}}=\sqrt{b}$ we have that $\sqrt{b}\in L$. Now I want to look at $$\mathbb Q\subset K\subset K(\sqrt b)\subset L$$ and differentiate some cases. The case where $[L:K]=1$ is trivial and the case $[L:K]=4$ can't happen because if we square any root and subtract $a$, we get $\pm\sqrt{a^2-b}\in K$ which means $[L:K]\leq 2$. So let's look at the case where $[L:K]=2$. As I see it, we get two subcases:   For $[L:K(\sqrt b)]=2$ we have $K(\sqrt b)=K$ which finishes the proof. For $[L:K(\sqrt b)]=1$ we have $K(\sqrt b)=L$. This means that $L$ is also the splitting field of $(x^2-b)(x^2-(a^2-b))$. Is this a contradiction? How do I finish this case? If $f \in L_p \cap L_q$, $1 \leq p < r < q < \infty$ then $f \in L_r$. If $f \in L_p \cap L_q$ and $1 \leq p &lt; r &lt; q &lt; \infty$ then $f \in L_r$.   Proof: Let $E = \{ x \in X: \left\lvert f \right\rvert \leq 1 \}$. Then, $$\int \left\lvert f \right\rvert^r \mathrm{d}\mu = \int_E \left\lvert f \right\rvert^r \mathrm{d}\mu+\int_{E^C} \left\lvert f \right\rvert^r \mathrm{d}\mu \leq \int_E \left\lvert f \right\rvert^p \mathrm{d}\mu+\int_{E^C} \left\lvert f \right\rvert^q \mathrm{d}\mu$$ $$\leq \int \left\lvert f \right\rvert^p \mathrm{d}\mu+\int \left\lvert f \right\rvert^q \mathrm{d}\mu &lt; \infty.$$ Thus, $f \in L_r$.  I just want to make sure I am somehow not missing anything. Thanks What are the differences between 32-bit and 64-bit, and which should I choose? What is the difference between 32-bit and 64-bit Ubuntu? I've heard the 64-bit platform performs better and can detect more than 4GB of RAM. Also, while some apps haven't ported to 64-bit yet, ia32-libs lets a 64-bit machine run them.  If so, why not promote 64-bit over 32-bit?