Hi Bill,

A bell curve (or Gaussian distribution) is easy because if you add together
a large number of random numbers taken from a uniformly-distributed
generator (like the type you describe), you will get some number, call it
x. If you repeat the process with different numbers from that generator and
get x2,x3,x4, etc., then the x's will have a distribution which
approximates a Gaussian. You can then get whatever standard dev. and mean
you want by just scaling and shifting the output. So, if the sequence
x,x2,x3,x4,.... has mean 0.5 and stdev 2, and you want mean=10 and sddev=6,
then the sequence 3*x+9.5,3*x2+9.5,3*x3+9.5,..... will have what you want.

I don't know how many numbers you will need to add together to generate
each output number, but from a some graphs I have in a book here, it looks
like about 10 to 20 would be adequate.

Sean

At 01:25 PM 5/7/00 PDT, you wrote:
>Speakinng of random numbers, I have a new (?) question.
>
>How do I generate random numbers with a nice statical distribution, ie
>ones that fit a standard bell-shaped curve.  Most random number generators
>try to generate all possible combinations in an even distribution, but what
>if I want numbers "near" "X", perhaps with a specified standard deviation...
>
>BillW
>
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| Sean Breheny
| Amateur Radio Callsign: KA3YXM
| Electrical Engineering Student
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