Plotting a discrete probability distribution
- To: mathgroup at smc.vnet.net
- Subject: [mg30531] Plotting a discrete probability distribution
- From: "OBrien-Malone" <dot at dot.dot>
- Date: Tue, 28 Aug 2001 04:54:36 -0400 (EDT)
- Organization: The University of Western Australia
- Sender: owner-wri-mathgroup at wolfram.com
This will sound strange, but I would like to plot values defined by the
function for the Poisson Distribution PDF, but for values that are not
integers, and therefore not strictly part of the PDF
PDF[PoissonDistribution[3],x] returns the function in x as one would expect,
namely
3^x/(E^3 * x!)
I can now substitute values for x using
/. x->valueWanted
and have the function evaluate at valueWanted, but
Plot[ PDF[PoissonDistribution[3],x], {x, 0, 5}]
does not produce anything.
Ah, I've just seen that I can do it with Evaluate around the PDF, but
(1) *why* do I need it, when I do not need it with NormalDistribution?
(2) If I want to evaluate (plot) values in the extremities of the
PoissonDistribution, how can I push the precision in this case beyond
MachinePrecision so that I do not just get zero?
--
Cheers
Mark R Diamond
--------------------------------------------------------------------------
Mark R Diamond
Vision Research Laboratory
Department of Psychology
The University of Western Australia
SPAM AVIODING EMAIL: ... at psy dot edu dot au, address to markd
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