I wanted to make use of some functions in 'stat.inc'. Looking through the file I see there are a few distributions in which p.d.f. and c.d.f. technically should be defined to have a value of zero for negative x. For example, exponential r.v.s, Weibull r.v.s and Rayleigh r.v.s have a support which is only the non-negative portion of the x-axis.
The way to address this would be to define
#
#define unit step function
#
u_step(x) = x<0 ? 0 : 1
then multiply all the pertinent density/distribution functions by the unit step.
Should I put together a patch for this?
Dan
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