RGB, Thanks for the references. Oh btw, the link to the C projects seems broken.
Nathan On Nov 20, 2007 2:23 PM, Robert G. Brown <[EMAIL PROTECTED]> wrote: > On Tue, 20 Nov 2007, Nathan Moore wrote: > > > After reflection though, I've started to wonder about the wisdom of my > > choice. Specifically (like RGB), I love the GSL library, and extending > GSL > > to fortran in an intro class is non-trivial. Additionally, most vendors > > supply "fast" hardware libraries in C (I may be ignorant, but if a > student > > wants to call an AMD ACML fast-math function( > > http://developer.amd.com/acml.jsp), or write a linear algebra function > to > > run on a graphics card(http://developer.nvidia.com/object/cuda.html), > the > > vendors seem to assume that you'll write the code in C). > > > > Also, and more relevant, I assume that most employers word-associate > > "Fortran is to backwards as C is to competence". > > > > So, I'm thinking about reworking the class to favor C, and fearing 3 > weeks > > of pointer and addressing hell. For those of you who teach scientific > > computation (and also those of you who hire undergrads), I'd be grateful > for > > your thoughts. One specific question I have is what text covers > scientific > > programming and touches on MPI using the C language. > > Ah, grasshopper, you have finally managed to snatch the stone. (Or is it > drink the kool-ade, I never can remember...;-) > > Let's see. There are some truly excellent books that have helped my > independent study students on programming (most of whom are trained in > Java only these days, God help us all:-( learn C. There are also two > free online C reference manuals, three if you count Gnu's (which > unfortunately is by far the worst of them). I will endeavor to provide > you with a short shopping list, as I keep pretty much a complete C > programmer's reference toolkit on my laptop at all times including the > two aforementioned C textbook/manuals, various other free/online > manuals, and of course the man pages. Even though I write a LOT of C I > still have to look things up -- what programmer doesn't? When I'm > online I have even more access to free resources as GIYF. > > To my mind, the most difficult aspect of programming in linux for a > newbie isn't the compiler, it is the programming environment and > learning how to create a project directory, put it under subversion (or > possibly CVS) control, pick a text editor (not a WYSIWYG WP, an editor, > ideally one that groks compilation and make), and write that first hello > world program. The second longest thing is teaching them a sane way of > getting variables off of the command line and into a program, especially > when some of the kids have never really used a command line at all in > the past. Drop the mice, guys -- fingers on those home keys! That's > where you type, after all... > > This process is greatly sped up if you provide them with a "standard > program template" like the one here: > > > http://www.phy.duke.edu/~rgb/General/project.php<http://www.phy.duke.edu/%7Ergb/General/project.php> > > which can create a work directory for you by running a little script and > prepopulate it with a functional Makefile and a set of hello-world > sources complete with a routine that parses the command line and can > fairly easily be hacked to add new CL arguments. Note that this > template is always changing and you'll like have to modify it and test > it to meet the needs of your students, but it will TREMENDOUSLY improve > your ability to grade projects as they can "make tgz" and ship you a > project tarball, ready to unpack, build, test. > > I personally like the jove (Jonathan's Own Version of Emacs) for all > text editing because emacs is maddeningly complex, crufted, overladen > with features, and hence all but unlearnable. jove installs easy, there > is a teachjove tutorial that will walk students through all they need to > know to use jove as a semi-IDE, and you're done. I've got jove > tarball/rpm's, or it is in debian ready to roll from what I've heard > (what isn't?:-). > > One of the two C books I'd recommend is here: > > > http://www.phy.duke.edu/~rgb/General/c_book.php<http://www.phy.duke.edu/%7Ergb/General/c_book.php> > > which is a legal mirror of the original book. Note well the license is > a "beer" license. You have to buy the authors beer if the opportunity > to do so presents itself. This may present problems for your students > if they are underage, but I imagine the authors of the book will be down > with that. So each student can mirror my mirror, or they can find the > original online with google or otherwise and mirror that. That way they > can have an entire, quite readable book on C, replete with cut-n-paste > examples, free, installed on their personal computers where it is always > handy and useful. > > This is a "beginner" level book -- complete enough for simple code, but > not really up to snuff on things like threads or advanced data > structures. For the SERIOUS student, or the student working on an > advanced project where forking, threads, and so on are necessary, I'd > recommend that they use Dave Marshall's book: > > http://www.cs.cf.ac.uk/Dave/C/CE.html > > This is a GREAT book. A full out, pro-grade book on C including some > very advanced stuff. Parts are a tiny bit dated -- the first chapter of > the book deals with CDE on Solaris -- but it is a killer reference. > Online access is free, and if you contact Dave regarding redistribution > of the book to a class full of students in PDF format (which he has, and > for that matter so do I) he might be open to it. He sent one to me > willingly enough when I asked him about it, so I've got it on my laptop > for eternity, network or not. He was going to look into a Gnu OPL for > it when last we communicated. At this point I'd suggest (to him) > throwing it up onto Lulu for cheap download in PDF or paper print with a > reasonable markup -- he'd make money and students would get a generally > lovely book in whatever form(s) they prefer. > > Then there are a variety of algorithm books or programming environment > books I like to recommend to students I'm teaching: > > * King Abel and Graham Glass's book. > > http://www.amazon.com/Linux-Programmers-Users-Graham-Glass/dp/0131857487 > > I've used this book since it was just glass and Unix instead of Linux. > A classic. Way too EXPENSIVE a classic at $84, but a classic. > > * Mastering Algorithms in C (O'Reilly Seahorse IIRC). Excellent > reference for stock-in-trade stuff like data structures, linked lists, > sorting, numerical methods (to a point). > > * Kernighan and Pike's The Practice of Programming. I'd actually make > this a requirement for any new C programmer. It covers things like > INDENT YOUR GODDAMN CODE AND I REALLY MEAN IT, and IF YOU DON'T COMMENT > YOUR CODE YOU WON'T UNDERSTAND IT YOURSELF TWO WEEKS FROM NOW, and WHAT > THE HELL IS aRp IN YOUR CODE? DOES THAT MEAN SOMETHING TO YOU ASIDE > BESIDES "BARF"? so that you don't have to yell QUITE so much at your > students and has lots of other wisdom as well. > > * Optionally Kernighan and Pike's The Unix Programming Environment > isn't quite as good as Abel and Glass, but it is still damn good and and > excellent reference. > > For numerical methods per se, well, there is STILL Numerical Recipes in > C, but I no longer use it in any code because it sucks in so many ways. > It is encumbered, with a code-reuse license out of the dark ages, I mean > a really, really, really bad one (in spite of the fact that some of the > code they are trying to encumber comes right out of the literature). I > personally think that all they need is the GSL itself and the GSL's > manual, online or otherwise. At this point anything you're at all > likely to have beginners doing is well-supported there, with > documentation and code examples, with a list to ask difficult questions > on. And yes, they can buy a paper copy of this from Amazon (and help > support the project at the same time). And it is even cheap. > > My actual favorite numerical methods book is alas in fortran -- > Forsythe, Malcom and Moler -- but all that they really need from any > such textbook is a two lecture discussion on discretization error and > bad ways of doing what appear to be straightforward tasks because > computers do discrete arithmetic. If the course were going to FOCUS on > numerical methods, e.g. derive a 4th-5th order RK ODE solver and code > it, you'd likely need t textbook to help, but to USE an RK ODE solver -- > just the GSL, just the GSL. > > The last reference I like to recommend is (of course) Knuth's TAOP. > 'Nuff said. Expensive as hell for the full set, but it IS the only > reference you'll ever need, unless you plan to do network programming in > which case you'll likely need one or more of Stevens' excellent books, > or plan to do systems programming at the kernel level, in which case > you'll need several books I'm not going to list here, or MPI or PVM, in > which case you'll need -- what? Well there are a few excellent books > from IIRC MIT press on them, but they may be dated at this point. There > are the many superb articles on www.clustermonkey.new and in the Linux > Magazine archives. Again, having a good template goes a long way -- > there is a PVM template on my website but I don't use MPI (or PVM, much, > anymore) so you'll have to get them from other folks. > > I've found that some subset of the *'d references and free references > above can take a student that can program in ANY language already and > make a credible C programmer out of them in a semester. > > And jeeze, man. Pointers rock. If you want students to actually learn > how computers work so that they can UNDERSTAND what they are doing they > are peerless (if painful) instruments of learning. Want a block of > memory? Go get it, lay it out, access it, all with fairly high level > commands. Want to overlay a secondary addressing scheme on top of it? > Sure, why not. Allocate a vector, pack its addressing into a ***pointer > to make a matrix[][][] that you can still pass to an ODE solver that > wants vectors only, while addressing it in a completely natural way in > the deriv evaluator. You can do things in C easily that you can't do AT > ALL in other languages, all because of pointers and the ability to > recast variables. Sure, you can break a program more horribly than you > ever could in Fortran (although I've managed to break fortran pretty > horribly). That's why you get them K&P and make them read it FIRST, and > why you teach them about adding > > > #define MYDEBUG(b) if ( (verbose == b) || (verbose == D_ALL) ) > > typedef enum { > D_QUIET, > D_ALL, > D_V_2, > D_V_3, > D_V_3, > N_DEBUG }; > > into their primary program header and sticking: > > x = 1.0; > MYDEBUG(D_V_1){ > fprintf(stderr,"# This is my subroutine 1, and variable x = %f\n",x); > } > > chunklets all over their damn code as they write it. Run the program as > > $myprog -v 2 > > and out spews: > > # This is my subroutine 1, and variable x = 1.000000 > > Run it as > > $myprog > > and it doesn't. I instrument my code so that at any instant I can get a > completely verbose picture of everything it is doing as it goes along, > or "zoom in" on just one subroutine. It is tricks like this that make C > programming robust and doable. One should do it in any language, of > course, but in C it is ESSENTIAL to make sure that the program is doing > what it is supposed to be doing, not overwriting array boundaries, and > so on. In fortran you are lulled into a false sense of security because > you THINK the compiler or runtime engine will catch errors for you when > in fact there are lots of errors they will miss, and then you are REALLY > dead. > > HTH, > > rgb > > > regards, > > > > Nathan Moore > > > > > > > > -- > Robert G. Brown > Duke University Dept. of Physics, Box 90305 > Durham, N.C. 27708-0305 > Phone(cell): 1-919-280-8443 > Web: http://www.phy.duke.edu/~rgb <http://www.phy.duke.edu/%7Ergb> > Lulu Bookstore: http://stores.lulu.com/store.php?fAcctID=877977 > -- - - - - - - - - - - - - - - - - - - - - - Nathan Moore Assistant Professor, Physics Winona State University AIM: nmoorewsu - - - - - - - - - - - - - - - - - - - - -
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