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From: dpb <none@non.net>
Newsgroups: comp.soft-sys.matlab
Subject: Re: matrix generation
Date: Sun, 08 Nov 2009 13:20:07 -0600
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dpb wrote:
> jack j wrote:
> ...
>> But what if the condition is something like " (1st column element-2nd
>> column element)+(3rd column element-4th column element)"for all rows
>> should be equal to x???
>>
>> In this case will such a defn work out?
> 
> Possibly depending on the size of the selection pool and value of x. The 
> rudimentary case for the above would be generate three independently and 
> solve for the fourth as the parentheses make no difference numerically 
> to the overall sum (and since you didn't state any other condition).
> 
> You'll have the same problem of occasionally (or more than occasionally, 
> perhaps) having to resample; whether that's acceptable or not on the 
> required population statistics or not is another question you'd have to 
> judge.

NOTA BENE:  In the above I assumed the "for all rows" means each row 
independently satisfies the criterion.

--