Re: restoring state of rand()

[David Bateman]

This is a bug. The problem is that you requested the state before it
was initialized, and so the vector v contains all zeros.. Try and

rand(3,1)
v = rand("state");
rand(3,1)
rand("state",v);
rand(3,1)

and you'll see what I mean... I just committed a patch to fix this..

D.

According to Michael Creel <address@hidden> (on 10/15/04):
> Hello,
> 
> "help rand" tells me that
> 
> <quote>
> You can query the state of the random number generator using the
> form
>           v = rand ("state")
> This returns a column vector V of length 625. Later, you can
> restore the random number generator to the state V using the form
>           rand ("state", v)
> </quote>
> 
> but my mileage varies:
> 
> octave:1> help rand
> octave:2> v = rand("state");
> octave:3> rand(3,1)
> ans =
> 
>   0.82058
>   0.29780
>   0.98109
> 
> octave:4> rand("state",v);
> octave:5> rand(3,1)
> ans =
> 
>    4.4409e-17
>    4.4409e-17
>    4.4409e-17
> 
> Can anyone help me out? I'm using octave-forge compiled against octave 2.1.57
> 
> Michael
> 
> 
> 
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-- 
David Bateman                                address@hidden
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