Re: rand function question

Joachim wrote:
Peter Perkins <Peter.PerkinsRemoveThis@xxxxxxxxxxxxx> wrote
Also, the period of the generator is _very_ long (2^19936
or thereabouts), so
while you might get repeated values in your lifetime, you
will not see the
sequence repeat any time in the foreseeable future.

Well, on my Matlab (R2007a/Linux x86), every time I fire up
Matlab and enter (as first command)

format long; rand

I get

ans =
0.814723686393179

I'm guessing you know the reason for this, but just in case:

>> help rand

[snip]

The sequence of numbers produced by RAND is determined by the internal
state of the generator. Setting the generator to the same fixed state
allows computations to be repeated. Setting the generator to different
states leads to unique computations, however, it does not improve any
statistical properties. Since MATLAB resets the state at start-up, RAND
will generate the same sequence of numbers in each session unless the
state is changed.
.

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