Curious if anyone has given Lush a try here? http://lush.sourceforge.net/ It's essentially a lisp-like way to write C, with lots of integration with libraries to do numerical computing, machine learning, etc.
Carson On Nov 24, 5:47 pm, CuppoJava <patrickli_2...@hotmail.com> wrote: > I must admit that even though I love Clojure and use it daily for many > things, I don't like using it very much for my research (machine > learning) which involves a lot of number crunching. > > The main reasons being: > > Numerical software involves a lot of array indexing, and loops, and > not much else. Clojure's functional data structures are elegant, but > are not quite fast enough for heavy numerical processing so I still > need to use native arrays. And if all I'm using is native arrays, the > java syntax for arrays is much easier on the eyes than a bunch of > nested s-exps. > > The other reason is that Clojure emphasizes functional programming and > discourages mutation. This is fine, as I believe well-written code is > usually functional anyway. The problem is that bad code is usually > easier to write in an imperative way than a functional way, and the > ability to write bad code is important I think. It's usually a lot > quicker to whip up a mutative hack than think through the problem and > factor out components and be functional about the whole thing. And > usually, in the very very early stages of programming something, when > you don't clearly know what it is you're programming, it's nice to be > able to whip out a quick and dirty mutative hack. And then make it > nice and elegant and functional later on, but Clojure makes doing that > difficult for me. > > -Patrick > > On Nov 24, 3:12 pm, Mike Meyer <mwm-keyword-googlegroups. > > 620...@mired.org> wrote: > > On Wed, 24 Nov 2010 09:20:49 -0800 (PST) > > > cej38 <junkerme...@gmail.com> wrote: > > > I am a physicist. I have been using Clojure full time for the last > > > year and a half. The reasons that Rich (and most other Clojure > > > evangelists) give for using Clojure, are all nice and good, but they > > > point to what computer scientists think about. If you want scientists > > > and engineers to think about switching to Clojure, you need to talk to > > > the concerns that they have. Of course, there is some overlap. > > > The thing is, I'm not sure it's the best choice for such people. At > > least, not yet. The LISP-like syntax means you have to explain the > > code if you publish it, a problem that some alternatives - which have > > most of your advantages - don't have. Look at Python, a descendant of > > ABC, which was designed for teaching/prototyping. It's been described > > as "executable pseudo-code". > > > > Here are some reasons that I would give for using clojure: > > > 1. Most data analysis gets done by writing little programs that do > > > certain tasks. When writing in Fortran I more or less have to write a > > > new program to do each task. In clojure, I might have to write a new > > > function, but I keep finding that functions that I wrote before, will > > > help with these new problems. Code re-use is much higher! Less time > > > coding. > > > I think this says more about your coding style than Clojure. I find > > that true in most of the languages I write in, but I structure > > programs to make it so. > > > > 2. fewer number of parameters that need to be passed into > > > subroutines. When writing fortran/C programs, you not only need to > > > pass in the data, but you also need to pass in parameters that > > > describe the data. In clojure, you usually only pass in the data. > > > The same is true of Python, and most modern languages. Clojure's data > > structures - which make this possible - have been around in other > > languages for quite a while now. > > > > 3. (related to 2) Everything is a function, thus, as long as the > > > inputs and outputs are the same, you can change the internals at > > > will. This makes it super easy to try rewriting code to make it run > > > faster. > > > The same is true of Python. > > > > 4. Using the REPL you write fewer bugs. In an imperative language you > > > have to make a guess as to how a whole (possibly very long) subroutine > > > should be written before writing it and then debug. Using the REPL > > > you start with the most basic steps of the subroutine, make sure those > > > work, and then continue to build until you have something that works. > > > This is also true of Python's REPL. > > > > 5. ease of changing function calls to allow for extra stuff/ > > > functionality without breaking other stuff. An example would be best > > > here. Suppose I had defined some function that worked for a specific > > > purpose: > > > (defn setzero [value] > > > "If value is less than 1.0E-8 setzero returns zero.." > > > (if (tolerance? value 1.0E-8) 0 value)) > > > The same is true of Python: > > > def setzero(value): > > "If value is less than 1.0E-8 setzero returns zero" > > return 0 if tolerance_p(value, 1.0E-8) else value > > > > and later I decided that I would really like to use that same function > > > again, but that 1.0E-8 won't work in this new case. I can change > > > setzero so that it will work with all of my old code (without change > > > to the old code) but I can make it work new code as well. > > > (defn setzero > > > "If value is less than parameter setzero returns zero. If no > > > parameter is specified, the default value of 1.0E-8 is used." > > > ([value] > > > (setzero value 1.0E-8)) > > > ([value parameter] > > > (if (tolerance? value 1.0E-8) 0 parameter))) > > > def setzero(value, parameter=1.0E-8): > > """If value is less than parameter setzero returns zero > > The default value of parameter is 1.0E-8""" > > return 0 if tolerance_p(value, parameter) else value > > > (ok, I followed the comment not the code) > > > > 6. Many types of Concurrency "without all that mucking about in" MPI, > > > openMP and the like (Thanks to Douglas Adams.) > > > Not true in Python. Worse yet, even the most recent versions of > > Python's C implementation still suffer with the GIL. This (along with > > just flat liking functional programming and LISPy languages) is why > > I'm looking at clojure. But as you say, these are a professional > > programmers reasons for using it; I'm not sure they carry enough > > weight to overcome the advantages Python (or other, similar languages) > > might offer. > > > > 7. Is it a scripting language or a compiled language? Yes. Depending > > > on what you need it for. I often use the REPL and my code to script > > > stuff. There are also times where you want to have a real program as > > > a JAR file, clojure can be both. > > > The same is true of Python. In fact, it's true twice: if you think > > that the JVM is fast enough, you can run your code in Jython and > > leverage Java tools. If that's not fast enough, you can wrap your > > favorite native FORTRAN libraries (assuming it hasn't already been > > done) along with a graphics library, and play with them all in the > > REPL. Not merely exploratory programming, but full-blown visual > > exploratory data analysis! (Yes, I know incanter does this kind of > > thing, but it doesn't seem quite as mature - and I believe it runs at > > JVM speeds.) > > > > 8. Every problem has been solved twice in Java. Meaning it has been > > > solved three times in clojure. > > > Java's a relative newcomer. If it's been solved twice in Java, it's > > probably been solved twice in Python, with wrapped C and C++ solutions > > available as well. This is not always a good thing... > > > > The underlying theme is that you can quickly write the code that you > > > need to do your job, so that you can get back to doing your job. > > > At this stage, I suspect that Python is still the better tool for > > them. The advantages Clojure has over Python are in the "for computer > > scientists" domain, whereas Python's advantages over Clojure are > > things that will matter to them: access to libraries they are familiar > > with, and that it's much easier to read Python code on first exposure, > > means that sharing results (an important part of the process) is much > > easier. > > > Especially since there's a community of people willing to help them > > with it athttp://www.scipy.org/. Of course, if you're trying to get > > them off FORTRAN, pretty much anything would be an improvement. > > > <mike > > -- > > Mike Meyer <m...@mired.org> http://www.mired.org/consulting.html > > Independent Network/Unix/Perforce consultant, email for more information. > > > O< ascii ribbon campaign - stop html mail -www.asciiribbon.org -- You received this message because you are subscribed to the Google Groups "Clojure" group. 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