I'm trying to understand why python has this unheard of behavior.  If I'm writing rawdata string, it is much more likely that I won't want escaping quotes.  This behavior forces us to write this weird code:  s = r'something' + '\\' instead of just 's = r'something\'  any ideas why python developers found this more sensible?  EDIT:  I'm not asking why it is so. I'm asking what makes this design decision, or if anyone finds any thing good in it.
Technically, any odd number of backslashes, as described in .  &gt;&gt;&gt; r'\'   File "&lt;stdin&gt;", line 1     r'\'        ^ SyntaxError: EOL while scanning string literal &gt;&gt;&gt; r'\\' '\\\\' &gt;&gt;&gt; r'\\\'   File "&lt;stdin&gt;", line 1     r'\\\'          ^ SyntaxError: EOL while scanning string literal   It seems like the parser could just treat backslashes in raw strings as regular characters (isn't that what raw strings are all about?), but I'm probably missing something obvious.
Prove  that the function $\displaystyle f(x)=\frac{x}{x^2+1}$ is continuous at $x=-1$. You should give a proof that is directly based on the  definition of continuity.   I saw many similar questions on this website, but none of them gave me a satisfactory answer. I more or less understand how epsilon-delta proofs work but my problem lies more in the algebraic manipulations probably. So here's my "attempt".  Definition of continuity; for $f:A \to \mathbb{R}$     $$\forall \varepsilon &gt;0 \ \exists\delta&gt;0\ \forall x \forall x_0 \in A:|x-x_0|&lt;\delta \Rightarrow |f(x)-f(x_0)|&lt;\varepsilon$$   So from what I understand, the procedure for epsilon-delta proofs are as follows: 1. Plug the point of interest $x_0$ into $|f(x)-f(x_0)|&lt;\varepsilon$ 2. Write $x$ in terms of $\varepsilon$ 3. Then plug $x$ into $|x-x_0|&lt;\delta$ 4. Find $\delta$ in terms of $\varepsilon$. Done    At step 1, we have $\left|\dfrac{x}{x^2+1}+\dfrac{1}{2}\right|&lt;\varepsilon$. Step 2 is where I'm stuck because of the 2nd degree polynomial in the denominator. First, I did this: $\left|\dfrac{x}{x^2+1}\right|&lt;\left|\dfrac{x}{x^2+1}+\dfrac{1}{2}\right|&lt;\varepsilon$. Then, I wasn't too sure about what to do, I thought about getting rid of the "$1$", but that would screw up my inequality. I thought about factoring $x^2+1$, but it doesn't have any real roots. I tried inverting the fraction, but that led me to nowhere. And I've already exhausted the tools I have. How do I proceed?  Apparently, epsilon-delta proofs are the most basic building blocks of analysis. And I'm already failing, this is both embarrassing and depressing... How to change Power button shutdown action to run a script under systemd Did J.R.R. Tolkien ever write a deeper connection between The Hobbit & Lord of the Rings: Fellowship of the ring? There seems to be a bit of a gap between The Hobbit and Lord of the Rings: Fellowship of the Ring. While we know the outcomes from The Hobbit to Lord of the Rings, we don't know what happened between them. Did Tolkien ever novelize this?  Connecting the two movies together, I've pieced the following sub-plots:   Saruman becomes corrupted by peering into the Palantír of Orthanc at some point after The Hobbit Gollum gets captured by Sauron's army Legolas leaves his homeland, in search of a ranger of some importance Tauriel is banished from her homeland Bilbo returns to the Shire, and finally relinquishes the one ring on his 111th birthday to Frodo   What doesn't seemed joined by the books or the two trilogy films:   How did a powerful white wizard like Saruman become enchanted/corrupted by Sauron What was Gollum doing before he was captured Where was Thranduil during the events of Lord of the Rings What happened to Tauriel during Lord of the Rings What happened to the remaining company of dwarves after The Hobbit Who now resides within Erebor What happened to Radagast during Lord of the Rings How to split a long regular expression into multiple lines in JavaScript? 2D and 3D vectors in Tikz I would like to draw some 2D and 3D vectors in Tikz with certain properties. The following primitive graph sums what I desire:   I just need the first quadrant of the Cartesian coordinate system for my representation.  I need the vector to be connected to the respective values on the distinct dimensions(not a projection, just orthogonal dashed lines).   The code segment below does what I want to achieve in 3D with two exceptions:  The projections on the xy plane and z dimension are given instead of connecting the head of the vector to the corresponding value in each dimension.  Numerical values are missing in dimensions.   Code: \documentclass[tikz]{standalone} \usepackage{tikz-3dplot} \begin{document}  \tdplotsetmaincoords{60}{120} \begin{tikzpicture}     [scale=3,     tdplot_main_coords,     axis/.style={-&gt;,blue,thick},     vector/.style={-stealth,red,very thick},     vector guide/.style={dashed,red,thick}]  %standard tikz coordinate definition using x, y, z coords \coordinate (O) at (0,0,0);  %tikz-3dplot coordinate definition using r, theta, phi coords \tdplotsetcoord{P}{.8}{55}{60}  %draw axes \draw[axis] (0,0,0) -- (1,0,0) node[anchor=north east]{$x$};     \draw[axis] (0,0,0) -- (0,1,0) node[anchor=north west]{$y$};     \draw[axis] (0,0,0) -- (0,0,1) node[anchor=south]{$z$};  %draw a vector from O to P \draw[vector] (O) -- (P);  %draw guide lines to components \draw[vector guide] (O) -- (Pxy); \draw[vector guide] (Pxy) -- (P); \end{tikzpicture} \end{document} I have several hundred Illustrator files that are formatted similarly, and for legal reasons I need to replace a font in all of them. Even with the 'Find font' tool, that's a hell of a lot of fonts to replace by hand.  Is there some way of automating it? For example, using Bridge? Illustrator (CS5) doesn't offer many options in Bridge, compared to the automation options offered by Photoshop. I also don't see any option for running actions on multiple Illustrator files.  Also, creating a repeatable action for replacing the font doesn't seem to work: instead of repeating my action, it brings up the dialog box an waits for me to tell it to replace them.  As a programmer I'm prepared to edit the files directly if it can be done without breaking them.    Update: The 'Batch...' menu item from Illustrator's actions panel menu allows the same action to be performed on a folder of files. It doesn't fix the Find Fonts action waiting for input though. Toggling the dialog off makes the action do nothing at all. Why singularity in a black hole, and not just "very dense"? Why does there have to be a singularity in a black hole, and not just a very dense lump of matter of finite size? If there's any such thing as granularity of space, couldn't the "singularity" be just the smallest possible size? How would I connect to a proxy on Ubuntu Studio? So I am running Ubuntu Studio on my laptop and what do I do to connect to a proxy? I search for proxy and in network settings their is no PROXY tab. What are key words in the tabs to look for? Stein's lemma condition (Apologies if I break some conventions, this is my first time posting!)  I am working on proving Stein's characterization of the Normal distribution: for Z $\sim N(0,1)$ and some differentiable function $f$ with $E[|f'(Z)|] &lt; \infty$, $$E[Zf(Z)] = E[f'(Z)]$$ Writing the LHS expression in integral form and integrating by parts, I eventually obtain: $$E[Zf(Z)] = \frac{1}{\sqrt{2\pi}} \left[ -f(z) \cdot \exp \left\{ \frac{-z^2}{2} \right\} \right] \Bigg|_{-\infty}^{\infty} + E[f'(Z)]$$ Now I need to show that the first expression on the right hand size is zero. Intuitively, this seems clear because of the exponential term, but I am having trouble explicitly applying the condition on $f'$ to prove this rigorously. Any ideas? , I shouldn't need to vote down or flag the answer, because the question itself is a dog.      Users should be allowed to also enable the "I'm done" button by down voting, close voting or flagging the question rather than directly taking action on the answer.    Currently, I have to click on the question's title, close or down vote it in the new tab, then go back to the review page, and click "Not sure" to continue on my adventure. What's the difference between using > and >> in shell? How can I improve Ubuntu overall system performance? extract value between two search patterns on same line I recently wanted to add some RAM to my old computer, but unfortunately I mixed together "good" RAM with chips that I extracted from a computer that failed after getting too much voltage. I know it sounds like a bad idea to just plug it into a motherboard, so I figured I'd ask first - is there usually any protection in the motherboards against this kind of faulty chips? Also, how likely is that RAM got damaged when computer got his deadly current or failed for internal reasons (something shorted because of dust, failed components etc.)? Is Borden's true identity real, or another ruse? Towards the end of , it's revealed that Borden accomplishes his Transported Man trick by using his twin brother, Fallon, as a double. It then becomes clear that he has been doing this in his personal life as well as on stage - each brother leads 'half a life', sometimes appearing as Borden and sometimes as Fallon. This is how he completes the illusion: one Borden goes into the first door, the other Borden emerges from the second door a moment later. Angier doesn't know how Borden does the trick, and doesn't believe Borden uses a double despite being told as much by Cutter. He follows what he believes to be a clue in Borden's notebook and travels to Colorado to meet Nikola Tesla, who Angier believes can build a machine that can help him perform the trick. Angier believes that Tesla built a similar machine for Borden. However, the final pages of the notebook reveal that Tesla was merely a red herring, designed to get Angier out of Borden's way for a long time. Tesla, it turns out, had never built such a machine before. At this point, Tesla agrees to build Angier's machine anyway. Instead of building a machine that transports matter, he builds one that duplicates it. Angier uses this machine in his act, but in order to avoid having to deal with multiple clones (the &quot;prestige materials&quot;), one of them must die as part of the act. This all makes sense, so far, but I find it hard to believe that Borden's use of the word 'Tesla' as the key to his cipher is random. It's too coincidental that he sends Angier on a wild goose chase, but Angier returns with a working machine. A film that is otherwise so tightly plotted shouldn't rely on coincidence to move the narrative forward, so there must be something else going on. Is it possible that Borden cloned himself using Tesla's machine? I usually compress my tex PDFs with ghostscript:  pdflatex -shell-escape file.tex  gs -sDEVICE=pdfwrite        \    -dCompatibilityLevel=1.4   \    -dPDFSETTINGS=/prepress      \    -dNOPAUSE -dQUIET -dBATCH      \    -sOutputFile=file_compressed.pdf \     file.pdf   Normally that works well, but if I have relative links to local files, the links don't work afterwards.  Minimal example:  \documentclass{beamer} \usepackage{hyperref}  \begin{document}     \begin{frame}         \href{run:./audio.mp3}{test}     \end{frame} \end{document}   The link works in file.pdf but not in file_compressed.pdf. Is there any pdflatex or ghostscript setting that retains the link in the compressed version?  I use Acrobate Reader 10.1.14 for viewing, Ghostscript 9.10 and pdfTeX 3.14159265-2.6-1.40.15 (TeX Live 2014) on OS X 10.9.5.    Update: The breakage of hyperlinks had nothing to do with compressing the PDFs. The breakage happened for all re-processing of PDFs containing hyperlinks in its input PDF. For what $n$ is $U_n$ cyclic? When can we say a multiplicative group of integers modulo $n$, i.e., $U_n$ is  cyclic?   $$U_n=\{a \in\mathbb  Z_n \mid \gcd(a,n)=1 \}$$  I searched the internet but did not get a clear idea. Why can't I use switch statement on a String? Output the common lines (similarities) of two text files (the opposite of diff)? Diff is a great tool to display the changes between two files. But how to display the similarities of two text files (while ignoring the differences)?  I.e. sample input:  a: Foo Bar X Hello World 42  b: Foo Baz Hello World 23   Pseudo output (something like this):  @@ 2,3 =Hello World   Just sorting both files and using comm is not enough, because in that case the line information is lost. How to Implement Page Object and Page Factory Pattern in Selenium Webdriver? I am a beginner in learning selenium Webdriver. I am not able to understand how page object and factory models works and how it can be beneficial?    Kindly help me explain it with detailed explanation.