# [Patches] [ python-Patches-1681432 ] Add triangular distribution to random

Fri Mar 16 09:57:45 CET 2007

```Patches item #1681432, was opened at 2007-03-15 14:09
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https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1681432&group_id=5470

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Category: Library (Lib)
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Wladmir van der Laan (miathan6)
Assigned to: Nobody/Anonymous (nobody)
Summary: Add triangular distribution to random

Initial Comment:
This patch adds the so called Triangular distribution for random values. It is often used in simulations when an upper and lower bound is known, and a most likely value but not the exact distribution. This distribution interpolates these values linearly.

http://en.wikipedia.org/wiki/Triangular_distribution

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>Comment By: Wladmir van der Laan (miathan6)
Date: 2007-03-16 09:57

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Yes, I will add some tests and docs, although usage is quite
straightforward. That's the main reason also for adding this distribution,
it has three parameters which are intuitive (left, center and right) the
distribution is just a linear interpolation (P(left)=0 and P(center)=1 and
P(right)=0 ).

I am writing an event simulation and I added it because I was missing some
kind of assymetric distribution for timings; in an uniform distribution t-x
and t+y would be just as likely as t, in a gaussian distribution you can
only set sigma but not the upper and lower bound.

With all the other distributions in there I thought it might come in handy
for other people too. I also believe it has its uses in sound
generation/processing.

Sorry for providing a patch against 2.3 and not 2.5 or higher, I cooked it
up at work and it seems I have this ancient version here.

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Comment By: Collin Winter (collinwinter)
Date: 2007-03-16 03:22

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Could you work up some tests (Lib/test/test_random.py) and docs
(Doc/lib/librandom.tex) for this? An explanation of why you think this
should be included in the standard library would be helpful, too.

Also, it seems you made this patch against Python 2.3. While this
particular patch still applied (relatively) cleanly to Python 2.6a0 source,
Python 2.3 is no longer supported and most patches made against it have a
high probability of inapplicability. See http://www.python.org/dev/faq/ for
information on how to obtain a read-only checkout of the latest source
code.

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