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PDL 2.4.0: Scientific Computing for the Masses
Dr. Zowie writes "Perl Data Language 2.4.0 was just released;
get it here. This release includes even more powerful array slicing, a complete GIS cartography package, API access to the Gnu Scientific Library, and a host of other goodies. Between PDL and its less-mature siblings Numeric Python and Octave, the established commercial languages'
days appear numbered."
Another open-source statistical language is R. Its commercial cousin is S-Plus.
I use Octave at home to test anything I'm doing for the "Matlab" sections of my homework. And while I think it's a great program and works well, for large computations Matlab is much much faster. There is one routine in particular that takes about 4 hours to run at home and only 15 minutes to run at school. And no, this isn't because my home machine is P-MMX 100 and school has has 3GHz P-4's. The machines are pretty closely matched.
-1: flamebait should really be -1: inciteful
Well, I don't know about how mature/not mature Scientific Python or Octave are with respect to PDL, but I like Python better and I was used to Matlab in the past anyway.
At present, I am using Scipy, a nice more complete version of Numerical Python. Together with IPython, I get a very nice numerical environment. Unfortunately, while Scipy is very nice, it is still a bit of a bleeding edge product. But it is **very** fast for large array computations. I also like the fact that you can link fortran routines easily (yes, people still use fortran, it's useful and easy).
I also use Octave because I miss the ease of generating plots in Matlab (yes, I could do this with scipy, but somehow, I resort to using Octave). It is a very complete program, with many toolboxes. Given that some of the Matlab toolboxes can also be incorporated, there is a vast array of functions for you to play around with.
On the other hand, I think that none of the "established languages" are a good comparison. IDL is extremely powerful for Remote Sensing/Image Processing tasks (my area of research). It is simple to use, and a bit of a standard in the field. From the PDL changelog, the cartographic features in PDL amount to no more than transformations... Mathematica is extremely powerful in symbolic Maths, which as far as I can tell, is not what pdl is about. And Matlab is turning into the VB of scientists (at least, it is multiplatform :D)
Oh well, I'll have to give it a go :-D
Download it. In the tarball is
PDL-2.4.0/Demos/Cartography_demo.pm
All of these tools address different aspects of numerical computing. A mixture of languages and tools will generally produce the best results.
I've been experimenting with a number of scientific programming packages, ranging from traditional languages like Fortran 95 to new developments like SciPy. Of the "new" approaches, I like SciPy the best, given its support for MPI and ease of linking to traditional languages.
Support for NUMA and SMP architectures is severely lacking in most "free" packages. This may, in some respects, be due to the lack of parallel support on gcc (although there is an effort underway (gomp) to add OpenMP support to gcc).
Parallelism is important to any large-scale numerical application -- and PDL, as yet, does not appear to support SMP, NUMA, or cluster architectures. I know there are attempts at adding parallel support to Perl, but haven't seen much activity with them.
GSL does not implement any parallel algorithms; according to this post by Brian Gough (), GSL is not designed to support parallelism.
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