Explain this one line of code

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Can anyone explain to me this one line, what actually this one line do ?
rand('state',sum(100*clock)); % resetting of the random table

Accepted Answer

Star Strider
Star Strider on 7 Jul 2014
It’s an obsolete way of resetting the seed of the random number generator. See the documentation on Replace Discouraged Syntaxes of rand and randn for details.
Star Strider
Star Strider on 7 Jul 2014
Yes. It’s set up in that statement to set the seed based on the current time (the sum of the elements in the six-element date vector returned by clock).

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More Answers (2)

Ben11 on 7 Jul 2014
I think this ensures that random numbers generated from different calls are all different since you use the current date/time in your call. You might want to take a look at this:
in which The Mathworks discourages using this syntax and proposes alternatives.

Shashank Prasanna
Shashank Prasanna on 7 Jul 2014
Edited: Shashank Prasanna on 7 Jul 2014
Aftab, Random number generators are really pseudorandom (deterministic). This means for a given "seed" you can consistently regenerate the same sequence. This is useful if you want to re-run your experiment or perform multiple experiments on the same random stream.
In short, yes, using clock to reset the seed with generate a different stream each time since the clock is different each moment. However the recommended way to change the seed is to use the RNG function:
Also all the link provided by SS and Ben are relevant.


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