Re^5: Randomly biased, random numbers.

You more or less have it.

I haven't a clue how I'd go about it though :( (Offers?:)

For my standard consulting rate? ;-)

Basically, you want to take a uniform distribution between 0 and M, and map it to a non-uniform one between 0 and N, so that X+I < X+J when I < J. One way to do this is to generate a ~~step-function~~piecewise linear function, then translate values through that ~~step~~ function. In Matlab, it looks something like this for a 10-step function:

fx = [0,cumsum(unifrnd(0,1,1,10))];
tmp=unifrnd(1,10,1,1e5);
ix=floor(tmp);
dx=rem(tmp,1);
values = (fx(ix) + (fx(ix+1)-fx(ix)).*dx)./fx(end-1);
[download]

Using a spline would be more complicated, but would be smoother.

Comment on Re^5: Randomly biased, random numbers. Download Code

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Re^6: Randomly biased, random numbers. by BrowserUk (Patriarch) on Dec 06, 2013 at 06:57 UTC
In Matlab, it looks something like this for a 10-step function: Great, thanks. Now all I gotta do is translate that from matlab, a lingo I am not familiar with. Darn it. Fell at the first hurdle. I cannot sense of your parameters to unifrnd()? With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^7: Randomly biased, random numbers. by educated_foo (Vicar) on Dec 06, 2013 at 07:04 UTC
Sorry -- it's much terser than Perl for math. `unifrnd(MIN, MAX, ROWS, COLUMNS); # uniform random numbers in [MIN,MAX +) cumsum(VECTOR) = #cumulative sum of vector # .OP = element-wise application of OP to operands` [download]	[reply] [d/l]
Re^8: Randomly biased, random numbers. by BrowserUk (Patriarch) on Dec 06, 2013 at 09:13 UTC
Is this `fx(ix)` (roughly) equivalent to this: `@fx[ @ix ]`? If it is, then I don't understand how you can index the 10-element fx with the 1e5-element ix? With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l] [select]
Re^9: Randomly biased, random numbers. by educated_foo (Vicar) on Dec 06, 2013 at 19:48 UTC
Re^10: Randomly biased, random numbers. by BrowserUk (Patriarch) on Dec 06, 2013 at 20:30 UTC
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