[PD] Issue with Gaussian Noise
martin.peach at sympatico.ca
Wed Aug 11 06:17:14 CEST 2010
On 2010-08-10 04:32, Frank Barknecht wrote:
> I made two generators for Gaussian white noise, one using DSP, the other
> as message based version. Both use the same algorithm, but the histogram
> analysis of both shows a defect with the message version: The histogram
> has a visible "valley" around the central expectation value, so it
> doesn't look like a real gaussian bell curve anymore.
> The message version is based on [random] not [noise~], and I "faked" a
> true frand by taking and scaling random values from the range 0-100000.
> Could this be the reason for the valleys or is the reason the custom
> algorithm [random] uses or is it, that two [random]s are not
> sufficiently independent?
Yes it is the reason for the valleys. Your random is on [-0.5,0.5]
instead of [-1,1]. The random needs to be multiplied by 2 million before
subtracting one million then dividing by one million. Then it works.
Also an uncertain execution order in the log divide part needs one of
The DSP version looks normal to me if I sample it a few times.
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