1. for anyone using QtMultimedia QAudioInput with python’s wave module to write PCM data to a wave file: to convert between QAudioFormat’s sampleSize() number and wave’s sample width number, divide by 8, e.g:

    wave_file_to_write.setsampwidth(audio_format.sampleSize() / 8)

    QAudioFormat’s sampleRate() number works as it is.

  2. Just realised that increasing the dimensions of an element onscreen when it is hovered over creates a “natural”, visual schmitt trigger effect.

  3. New policy: refuse to make significant changes to systems built under time pressure until they are fully understood, i.e. have been refactored, have good test coverage etc.

  4. Any ideas why the Icelandic locale in +natsort doesn’t correctly sort Icelandic characters alphabetically (aábcdðeé etc)? I just implemented a rather awkward hacky way of sorting them using the alphabet and natsort.versorted, but would rather find a way to correct the root issue.

  5. Today’s lesson: be VERY careful with programmatic use of contribute_to_class(). It doesn’t overwrite existing fields of the same name, resulting in intriguing errors when the ORM tries to do a SELECT query containing the same columns hundreds of times over…

  6. Finally solved a long-standing problem getting Icelandic characters to work properly in files being downloaded onto Windows machines for use as SPSS syntax. Turns out the solution is to explicitly set the download charset to UTF-8, and to prepend an unnecessary BOM (yuk) to the beginning of the file as so (context: Django view):

    import codecs
    def export_spss(request):
        response = HttpResponse(export_spss(), status=200, mimetype="application/x-spss; charset=utf-8")
        response['Content-Disposition'] = 'attachment; filename=syntax.sps'
        response.content = codecs.BOM_UTF8 + response.content
        return response

    Why is a BOM, which should be completely unnecessary in a UTF-8 file (it has no variable byte order after all) apparently required by some Windows software in order to tell it that the file is UTF-8 encoded, despite Unicode mode being on? Sigh.

  7. IE doesn’t upload csv files with text/* media type. Content-type cannot be trusted, the only way of telling if data is of a particular type is to see if it parses successfully.

  8. Today in “things I have typed instead of import”: imprto, improt, implore

    I actually quite like how implore pandas looks in my code.

  9. I’m getting too used to (puredata.info) — I just right-clicked a python class and expected a hypermedia “help” option with params, example usage etc.

    Jetbrains PyCharm does have an inline documentation feature, which (when invoked via a complex keyboard “shortcut”), produces this gem:

    Even when this feature does work, it shows code “documentation” in a monospace font, typically with no usage example or links to other relevant documentation, as is standard in puredata.

    Our tools are inadequate.

    Update: added puredata documentation for comparison:

    In case it’s not clear from the screenshot, that usage example is live code — it can be interacted with, changed, copied and pasted, played with, experimented with. We typically can’t do that with existing text-based code, let alone mere usage examples.

    More thoughts I want to add to this, but I will write them up as a full article.

  10. My first puredata patch: Canoner! A cross between a delay and a looper, this patch allows you to play canons solo.

    Hit Start/Round as you start playing, then again at a round point, and the patch will continue to play what you played with that delay until you hit Stop.

    Extending the canoner to support n>2 part canons is left as an exercise for the reader.

    Patch code:

    #N canvas 405 217 363 240 10;
    #X obj 26 34 tgl 40 0 empty empty empty 17 7 0 10 -204786 -1 -1 0 1
    #X obj 26 84 route 1 0;
    #X obj 214 201 delwrite~ round 10000;
    #X obj 214 176 adc~;
    #X obj 26 117 timer;
    #X obj 26 148 delread~ round;
    #X obj 26 198 dac~;
    #X floatatom 165 149 5 0 0 0 - - -;
    #X floatatom 129 149 5 0 0 0 - - -;
    #X obj 26 174 *~ 0;
    #X obj 101 34 bng 40 250 50 0 empty empty empty 17 7 0 10 -260097 -1
    #X text 13 15 Start/Round;
    #X text 106 14 Stop;
    #X text 249 176 Input Stage;
    #X connect 0 0 1 0;
    #X connect 1 0 4 0;
    #X connect 1 1 4 1;
    #X connect 1 1 8 0;
    #X connect 3 0 2 0;
    #X connect 4 0 5 0;
    #X connect 5 0 9 0;
    #X connect 7 0 9 1;
    #X connect 8 0 9 1;
    #X connect 9 0 6 0;
    #X connect 9 0 6 1;
    #X connect 10 0 7 0;

  11. There’s something incredibly satisfying, if a little masochistic, about poring over PIC datasheets and manpages, and tinkering with low-level code you only half understand, when it all actually works and you get two devices to talk to each other (in this case a PIC16F886 and a Raspberry Pi, via I2C)