[pstricks] Drawing S- and Z-Curves
Rich Shepard
rshepard at appl-ecosys.com
Wed Apr 22 01:56:32 CEST 2009
On Tue, 21 Apr 2009, Michael Sharpe wrote:
> For the bell shaped curve with value 1 at x=m, variance v, plotted
> from x=a to x=b, you could use
> \psplot[algebraic]{a}{b}{Ex(-(x-m)^2/v)}
> where, of course, specific numbers should be substituted for m, v, a, b.
> A similar expression can be constructed for the particular logistic
> curve (S-curve) you need, possibly expressed most simply using \tanh,
> written th in algebraic formulas. Eg
> \psplot[algebraic]{a}{b}{(1+th(x/2))/2}
Michael,
Yes, these will certainly work. The Z-curve will then be the inverse of
the S-curve. That's what I've done in python, but I did not know the
appropriate PSTricks approach.
Many thanks,
Rich
--
Richard B. Shepard, Ph.D. | Integrity Credibility
Applied Ecosystem Services, Inc. | Innovation
<http://www.appl-ecosys.com> Voice: 503-667-4517 Fax: 503-667-8863
More information about the PSTricks
mailing list