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Multiple use of Set on lists
Posted:
Jun 20, 2011 6:51 PM


Hello,
I have a largish list of awkwardly "indexed variables", of the form cs = {c[1/2][(1/2)][1/2][(1/2)][1], c[1/2][(1/2)][1/2][1/2][1]......etc.... ....} which need to be assigned random values multiple times inside a Do loop. I was hoping I could generate a new list of random numbers each time then do something like
MapThread[Set, {cs, rands}]
Where "rands" would be the list of random numbers. I'm clearly misunderstanding how MapThread works though as this doesn't work. Rather than getting "c[1/2][(1/2)][1/2][(1/2)][1]=new random number", instead "old random number=new random number" is what seems to be happening.
As a last resort I thought I would just clear the variables at the beginning of the do loop but you can't use Clear to do this and I don't see how you can apply "=." (Unset) over a list either.
Any suggestions?
Many thanks,
Jonny



