Explain this one line of code

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Hi,
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.
  2 Comments
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
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:
rng('shuffle')
Also all the link provided by SS and Ben are relevant.

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