* Alf P. Steinbach:
* Steve Holden:
Alf P. Steinbach wrote:
* Steve Holden:
Alf P. Steinbach wrote:
* Grant Edwards:
On 2010-01-15, Steve Holden <st...@holdenweb.com> wrote:
I will, however, observe that your definition of a square wave is
what I
would have to call a "'square' wave" (and would prefer to call a
"pulse
train"), as I envisage a square wave as a waveform having a 50% duty
cycle, as in
___ ___
| | | |
| | | |
| | | |
+---+---+---+---+ and so on ad infinitum, (though I might allow you
| | | | to adjust the position
| | | | of y=0 if you want)
|___| |___|
That is a square wave.
as opposed to your
_
| |
| |
______| |______ ______
| |
| |
|_|
That isn't.
Arguing to the contrary is just being Humpty Dumpty...
Neither I nor Steve has called that latter wave a square wave.
Steve, quoted above, has written that I defined a square wave that
way.
I have not. So Steve's statement is a misrepresentation (I
described it
as a sum of two square waves, which it is), whatever the reason for
that
misrepresentation.
[snip]
So here you have an interesting example of a
piece of code that is pathological in Python2. All you have to change is
to add
from __future__ import __division__
and bingo! It's a multi-language program. But try seeing what 2to3 says
about your Python3 code :)
I will forgive you the omission of the ".0" because I too would assume
that it would be slower.
I did not make any such assumption, no. The *1 just lingered from some
testing.
[snip]
and so on, but I still get silence from the Quicktime player.
I don't know, sorry.
It might be that [simple_sound] also needs the "from __future__" treatment.
But anyway, with 2.x compatible code you can now see that the sample
values produced are correct (just print them, or graph them).
I have now installed CPython 2.6.4 and the code presented upthread (the one with
divisions fixed for 2.x compatibility) worked nicely with CPython 2.6.4, even
though with a deprecation warning.
It produced the exact same sound file (bytes) as with CPython 3.1.1.
And the QuickTime 7.3 player played it with no problem, a base A pure sinewave,
composed utterly of 50% duty cycle square waves, resounding in my headphones --
it also works with WinAmp 5.54, Windows Mediaplayer 10.00 and VLC 0.9.9, i.e.
I'm unable to reproduce the problem.
So I suspect that you may lack a suitable codec, or it might be a PEBKAC
problem?
Cheers & hth.,
- Alf
PS: I had expected some jaggies and such since I only divided the cycle into 100
intervals, but graphing the data in Excel it showed a perfect sine. :-)
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