>>>>> "CY" == C Y writes:
>> Raymond Toy writes:
>> > There was a patch for octave that used Rybicki's method for
>> > complex args, but it had some unexplained constants that I wanted
>> > to understand, and my local university library didn't seem to
>> > have the journal with Rybicki's article, so I didn't do anything
>> > about it.
CY> What journal/article was this? I can't seem to turn up much with
CY> google.
Numerical Recipes has the reference for it for Dawson's integral:
Rybicki, G.B. 1989, Computers in Physics, vol. 3, no. 2, pp 85-87.
And actually, Numerical Recipes in C, Section 13.11 has a derivation
and says the approximation is good over the entire plane. But it
doesn't give error bounds on the approximation.
Ray