Re: randn & state

num wrote:

I have run 2 sets of 10000 realizations on different machines. Both
sets have the same analysis code. However, after the analysis is
completed, I got the same results. I thought that Matlab uses random
seeds (state) by default.


The help for RAND is pretty clear about this.  The current version says,

    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.

and previous versions say something very similar.

Hope this helps.

- Peter Perkins
  The MathWorks, Inc.
.

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