I have this String c9e9a0f30c56fc4881f09b65070ecf6ad65f2a51bc910fd5 composed of hexadecimal characters only. Correct me if I'm wrong but a character on a String takes a byte for its representation right? But since a hexadecimal character fits in 4 bits I could fit two characters in a byte. Is there a simple way to do this in Java?  Thank you in advance! You guys rock!
I am looking for a way to convert a long string (from a dump), that represents hex values into a byte array.  I couldn't have phrased it better than the person that posted .  But to keep it original, I'll phrase it my own way: suppose I have a string "00A0BF" that I would like interpreted as the  byte[] {0x00,0xA0,0xBf}   what should I do?  I am a Java novice and ended up using BigInteger and watching out for leading hex zeros. But I think it is ugly and I am sure I am missing something simple.
Let $R$ be the subring of $M_2(\mathbb{R})$ defined by $$R=\left\{\begin{pmatrix}a&amp;b\\0&amp;d\end{pmatrix}\mid a\in\mathbb{Q},b,d\in\mathbb{R}\right\}$$  Show that $R$ is right-Artinian but not left-Artinian.  The "obvious" approach to show it is not left-Artinian is to find an $A\in R$ such that $$RA\supset R(A^2)\supset R(A^3)\supset\dots$$  is an infinite decreasing chain of proper left submodules of $R$ (as a module over itself). However, after spending a lot of time in this endeavor I've come to the conclusion that no such element $A$ exists (I can post a proof if anybody is interested but it'd be long and not worth the time for me otherwise). Does anybody have an idea for another approach I can take to this? I have no idea what else submodules of $R$ would look like. Why does prime factorization for LCM work? A method to finding the LCM of two numbers is to use prime factoring. I know how to do this, but logically why does this work in finding the lcm Terminal not displaying colors for directory listings Do you capitalize both parts of a hyphenated word in a title?  "My Ex-Wife Hates Me"  or  "My Ex-wife Hates Me" SQlite: select into? I read this story a long time ago and cannot remember either the title or the author. It was written in the 60s or 70s. The setting is sometime in the 21 century.  Here is a summary of the plot.  One of the great classical composers (maybe it was Schubert, I'm not sure) is revived with some future technology. All the guys in the lab are very happy about it, the world cheers the achievement. The composer is also quite excited to be alive. Naturally, he is asked to perform a concert. He asks for ink and music paper. Nobody knows what that is: in those days everybody writes music directly in "frequency spectrum" and similar stuff.  The composer, excited to create music again, tries to come up with something but he doesn't like anything he writes. The music is well written, but lacks something essential, it doesn't sound like his real music. Finally, the composer realizes that the lab guys recreated his mind from reviews by music critics, and his music just sounds like that. He performs the concert. The audience enjoys it, applauds and bravos. Not only to composer, but also to the lab guys.   At the end, if I remember it right, the composer gloats over the  primitive taste of the audience. The audience who writes music in frequency spectrum and applauds to lab guys at the music concert did not see the failure in the concert and ate it as it is.  Does someone recognize the story?  PS all the recent talk of advent of AI machines with Machine Learning algorithms reminded me of this story. How do I enable the "Universe" repository? What is so special about $\alpha=-1$ in the integral of $x^\alpha$? Of course, it is easy to see, that the integral (or the antiderivative) of $f(x) = 1/x$ is $\log(|x|)$ and of course for $\alpha\neq - 1$ the antiderivative of $f(x) = x^\alpha$ is $x^{\alpha+1}/(\alpha+1)$.  I was wondering if there is an intuitive (probably geometric) explanation why the case $\alpha=-1$ is so different and why the logarithm appears?  Some answers which I thought of but which are not convincing:   Taking the limit $\alpha=-1$ either from above or below lead to diverging functions. Some speciality of the case $\alpha=-1$ are that both asymptotes are non-integrable. However, the antidrivative is a local thing, and hence, shouldn't care about the behavior at infinity. How can one make Firefox ignore my GTK theme entirely? Deleting polygon defined area from raster layer in ArcGIS Desktop? Which tool do I use in ArcGIS 10.1 for Desktop to exclude areas covered by vector polygon layers from a raster layer?   I want to keep portions of the raster layers that exclude the portions covered by the vector layer. Is a match forfeited if a player refuses to leave after being sent off? I want to type Arabic text in Photoshop, but the text appears disjointed and the letters do not connect at all. For example محمد appears as م ح م د.   I'm using Photoshop CS6 on OSX Mountain Lion. Dual Channel RAM vs. Quad Channel RAM I just bought a motherboard that says it supports Dual-Channel RAM. The RAM I'm looking at says it's a "Quad-Channel Kit" . Will it work with my motherboard?  EDIT: Thanks all for the replies. Here is some more info:    Here is the RAM I'm looking at:    It all looks compatible to me, I just was curious about the four channel thing. I have asked this question before  The first guy solved it in a way, but  i would like to know is there any efficient way to do so, because i did the same for N = 13 and N = 15  which took long time.  This problem is from a pen and paper test, ZIO-2018 Can i solve it with an efficient algorithm, well i am pretty beginner in algos, so if there is one kindly descibe it how can i do so?  Thank you Is there any way to bring an egg to its natural state (not boiled) after you cook it? This is probably a stupid question, but I'm curious now after I opened the refrigerator looking for eggs to make a cake and there was only one and it was cooked. Is there any way to undo that, whether at home or an industrial way? Can anyone help me with a solution? Java - How to reduce the size of third-party jars to reduce the size of your application Is there a platform-agnostic and filesystem-agnostic method to obtain the full path of the directory from where a program is running using C/C++? Not to be confused with the current working directory. (Please don't suggest libraries unless they're standard ones like clib or STL.)  (If there's no platform/filesystem-agnostic method, suggestions that work in Windows and Linux for specific filesystems are welcome too.) Record a macro of windows commands Using Windows 7, is there an in-built or third-party method of recording windows commands and being able to play them back?  As a very basic example of what I would like to be able to do, imagine having two desktop themes that you like to alternate between. The Windows commands would be something like   Open personalisation applet select second theme ok   (I'm calling this a macro because of the equivalent capability in Word.) Travel to Ireland (Dublin) with U.K. Visitor visa