David Mertens

  • Posted Research on how module authors "negotiate" breaking changes in software package managers to David Mertens

    I am a subscriber to

  • Commented on These benchmarks seem wrong...
    From Chris Marshall, who had trouble signing in to Hi David, nice to see work again on C::Blocks. The mandelbrot algorithm is likely a pathological case for PDL-2.015 for a number of reasons: (1) PDL computations are basically memory...
  • Posted These benchmarks seem wrong... to David Mertens

    Back in the fall of 2013 I began working on a project called C::Blocks. After some very long detours the project is finally coming to fruition. I recently took it for a spin on a benchmark from the benchmarksgame. The results? Let's just say I was very surprised.

  • Commented on PDL features I'd like to see in Perl 6
    @Salvador, I have written quite a bit of autolooping code for PDL using PDL::PP. While I agree that it might be nice for the compiler to automatically figure things out, I have seen many circumstances in which the autolooping behavior...
  • Posted PDL features I'd like to see in Perl 6 to David Mertens

    I recently asked around #perl6 as to a mailing list where I might discuss PDL features that I'd like to see in Perl 6.

  • Posted How Perl + StickK helped me get organized to David Mertens

    The last three months have been some of the most professionally productive months I've had in years. In true Perl fashion, it all boils down to a Perl-related "hack" with

  • Commented on Ideas for | an Indian connecting platform
    I think any sort of community building is a wonderful effort, to be commended. Solving a low-density issue is a hard problem, and the internet-based solutions you suggest sound like good ones. I can think of two basic issues you...
  • Commented on playing with Cairo
    Hey Dmitry, Could this be sped up using PDL? As I'm sure you know, I would be *very* happy to have a Cairo-backed PDL::Graphics::Prima, so anything I can do to move this along I'll do. :-) Context for those unfamiliar:...
  • Posted DOIs for Perl Module tarballs, probably to David Mertens

    A while back, Mark Fisher wrote about DOIs. As an academic, I asked about how I might cite a DOI for some Perl work. I was recently made aware of two possibilities.

  • Posted Lexical closures with END blocks warn, but Just Work to David Mertens

    I was just impressed by the awesomeness of Perl. More testing revealed to me that "use 5.018" does not invoke "use warnings", which dampened my enthusiasm a little. But Perl is still pretty awesome. Here's the situation.

    I write lots of Prima GUI applications. In this one (a presentation i…

  • Commented on Perl and Me, Part 6: Perl Is Engineering <i>and</i> Art
    The first part of your post is beautiful! Thank you! The second, more rant-ish part of your post, is what I would say if I were as good a write as you: I have not one but two unpublished drafts...
  • Commented on On Readability
    brian - I happen to agree with you, which is why I think that the two languages are equivalent. I usually hear this argument coming from the Python folks, not the Perl folks....
  • Commented on What?! CUDA::Minimal... works?
    Well, the general rule is that CUDA in a virtual environment doesn't work because the virtual environment doesn't have direct access to the video hardware. Your best bet is to install Linux on the machine directly and install the necessary...
  • Commented on how I learned to plot a mandelbrot set
    @Dmitry - I have been thinking about this a bit lately. I suppose here is as good a forum as any for discussing some of my ideas. One idea I have is to revise PDL::PrimaImage so that Prima and PDL...
  • Posted What?! CUDA::Minimal... works? to David Mertens

    I wrote CUDA::Minimal back in late 2010/early 2011 and used it in some of my research before defending my Ph. D. dissertation in May of 2011. At my postdoc I didn't use parallel anything, so CUDA::Minimal languished. When I picked it…

  • Commented on how I learned to plot a mandelbrot set
    Dmitry, very nice! By the way, the first time I ever heard of Prima was because I once looked up other modules that used PDL. PDL::PrimaImage was one of the few, and I was happy to see it. So it's...
  • Commented on test
    Hello, Makoto. :-)...
  • Commented on Introducing Fetchware: package management for source code distributions.
    Very cool!...
  • Commented on OT: DataCite Recommends "doi:" Scheme Prefix
    Mark - I've been thinking lately about citing my Perl work in journal articles, specifically via a doi. Do you know if there is any doi provider for Perl modules? I strongly suspect not, but figured I'd check with somebody...
  • Commented on Using Stratopan Beta
    Wow. Wow. Thanks for showing this off! $Jeff += like, a million....
  • Commented on PDL::Graphics::PLplot become to be able to output png format in Windows Active Perl ppm
    Yuki - Thanks for posting the install instructions for Windows. I don't use Windows, but I know that PLplot can give trouble when it comes to installing it on Windows. Having the instructions publicly available is a great help....
  • Commented on PDL installation to Windows fail.
    Yuki - Chris Marshall, the current PDL release manager, is far and away the best resource for issues with PDL on Windows. It is best to send mail to the mailing list. To do that, you have to subscribe because...
  • Commented on (my) Marpa Best Practices
    Man, Marpa looks like such an awesome tool. It makes me wish I had a parsing problem to solve. And some day, when I do, I'll check it out. :-)...
  • Commented on List shortage of Perl
    @Code Monkey, thanks for the kind words. @Yuki, thanks for the apology. You are expressing a wish that Perl was used more for numerical work and I share that wish. I think the issue was that I misread your wish...
  • Commented on I try to use PDL::Stats, but Test failed.
    PDL just released a new version that is not binary compatible with older PDLs. I suspect that Maggie hasn't uploaded the latest outside of a dev release. I also need to update PDL::Drawing::Prima for the new version of PDL. Does...
  • Commented on List shortage of Perl
    Yuki - I cannot speak directly to your first three concerns, but I can speak to the last one. I have worked extremely hard over the last five years to make PDL better. When I started using PDL, I felt...
  • Commented on Backing up private data securely
    Check out BitTorrent Sync. I used to keep my work and home projects synchronized with git, but I found that I kept pushing incomplete work to my repo just so I could work on it at home. If you keep...
  • Commented on I want mop rest capability to define fast accessor
    Yuki - You really should look into XSAccessor. If you like it, you should push its use. It is *faster* than direct hash access due to crazy op tree fiddling. Seriously, check it out. As for what you want, what...
  • Commented on PDL 2.007 Released!
    Hurray! Thanks Joel for posting this! 64-bit support FTW! chm++ @Yuki - Yes, when most people have a problem to solve for which PDL would be well suited, they think of Matlab, numpy, R, or XS/C. Why not PDL? I’m...
  • Commented on Am I pandering to the smoke testers?
    @Jeffrey - Actually, I *can* run the compiled tcc executable. The test suite invokes a great many C test programs through tcc, which is a binary built by the distribution itself, so it looks like Nigel's setup does indeed allow...
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  • Buddy Burden commented on Perl and Me, Part 6: Perl Is Engineering <i>and</i> Art

    animatedream: Thanks for your comment!  Good to hear from someone on the Python side of things.

    > First, I would never argue that python makes it hard to write bad code.

    I understand that.  The problem is, the person who literally wrote the book on Python made that exact argument.

    > I don’t understand the benefit to software development in being able to express a meaning in any way but the best way.

    Well, I suppose if there were always exactly one “best way,” not only to all people, but also in all situations, in all …

  • 6ae7ba33-d12b-49cf-89f9-34434fe68707 [] commented on PDL features I'd like to see in Perl 6

    smls here. (Using stackexchange OpenID since logging in normally is borked right now for me.)

    Type checks against array dimensions/sizes

    This seems to be firmly planned, but not yet implemented:

    ➜ perl6 -e 'sub foo (@a($x, $y)) { ... };'
    ===SORRY!=== Error while compiling -e
    Shape declaration with () is reserved

    Aliasing slices

    The following already works in Perl 6 right now (with Rakudo on MoarVM):

    my int @a = 2, 4, 6, 8; # create a compact native array
    my @b := @a[1, 3];      # take a slice, and bind …
  • Aristotle commented on PDL features I'd like to see in Perl 6

    I think the new refaliasing feature (experimental in 5.22) will allow you to alias slices like so:

    \( @slice[ 0 .. 4 ] ) = \( @data[ 2, 3, 5, 7, 11 ] );

    Obviously it’s ugly to have to count out the LHS slice by hand:

    \( @slice[ 0 .. $#$_ ] ) = \( @data[ @$_ ] )
        for [2, 3, 5, 7, 11];

    That’s quite a mouthful, but at least you can package it up in a function:

    sub alias_slice {
        my ( $src, @dst ) = shift;
        \( @dst[ 0 .. $#_ ] ) = \( @$src[ @_ ] );

    \my @slice = al…

  • therflabs commented on PDL features I'd like to see in Perl 6

    Call me crazy, but I had a freelance gig converting Python numpy/scipy to Perl PDL... And barely knowing Python it was a lot easier to understand than PDL.

    I can see why numpy/scipy has gained a lot of traction.

    I'd like to see P6 PDL to be like numpy/scipy to ease crossover to Perl 6 and lower the entry level for beginners. In my opinion usability and clear documentation for the non-math scholar has hurt what PDL could have been and could be a lesson for PDL Perl 6.

  • PetaMem commented on What?! CUDA::Minimal... works?

    And here's this - with Perl 5.22, GCC 5.3.0, CUDA 7.5 anno domini 2016:
    # ./Build test
    t/00_load.t ............... ok   
    t/Index-Manipulation.t .... ok   
    t/Memory.t ................ ok   
    t/Transfer.t .............. ok     
    t/z_PDL.t ................. ok     
    t/z_kernel_invocations.t .. ok    
    All tests successful.
    Files=6, Tests=76,  1 wallclock secs ( 0.02 usr  0.01 sys +  0.21 cusr  0.74 csys =  0.98 CPU)
    Result: PASS

    You have to do some hacking

    to remain silent about gcc …

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