[NTG-context] mp: choose colors randomly from list

Alan BRASLAU alan.braslau at cea.fr
Wed Feb 19 15:36:35 CET 2014

```On Wed, 19 Feb 2014 12:38:38 +0100
Schmitz Thomas A. <thomas.schmitz at uni-bonn.de> wrote:

> Not only I’m bad at math, I don’t even remember the answers to my own
> questions - thanks Wolfgang for reminding me! I’m getting old and
> senile, should look into early retirement...

The random numbers generated are deterministic, that is each run will
reproduce the same "random" sequence. If you are looking for more
randomness, then you need to set "randomseed := numeric expression ;"
using something that varies in a less predictable manner. For example,
you can set
randomseed := minute ;
where minute is the number of minutes past the hour of when the job was
started. So unless you have the habit of always processing your file at
the same minute of the hour, then your colors will vary.

Of course, if you want a truly random variable, then you need to use
some other physical process, like detecting the moment of passage of

One point of view is that chance is simply a reflection of our limited
knowledge, our "bounded rationality". The classical expression of this
is due to Laplace:
\startquotation
All events, even those that, because of their insignificance, seem
not to be governed by the great laws of nature, are a consequence as
necessary as the revolution of the Sun. Through our ignorance of their
relationship to the system of the universe as a whole, we have them
depend on some cause or on chance, according to whether they appear to
occur with some regularity or not; But these imaginary causes have
successively diminished with the advance of the limits of our
knowledge, and disappear entirely before a sound philosophical analysis
who sees in them but an expression of our ignorance, for which we
ourselves are the real cause.
\stopquotation

Quantum mechanics has revised this point of view. However, you are the
classicist, and according to Aristote an accident (συμβεβηκός) or
chance (τὺχη αὐτόματον) or (σύμπτωμα) is just an encounter of two
independent casual series. (And here I am exposing MY ignorance of
Greek!) :)

Alan
```