integral competition HP50g vs. DM42

[Didier Lachieze]

(08-23-2020 08:56 AM)peacecalc Wrote:  @stevetuc, I don't understand your code, although I'm familiar with RPN, for example what does "ZGHF" mean.

The 41C code above is not from stevetuc but from Angel Martin, ZHGF is a function from Angel's 41Z Deluxe module, an amazing Complex Number module for the HP-41:
ZHGF - Complex Hypergeometric function - Author: Jean-Marc Baillard

The 41Z Deluxe module image can be loaded on the 41CL, on the DM41X, or on a Clonix module to be used with a standard 41C/CV/CX. It requires the Library4 module to work.

You can find the 41Z Deluxe module manual here.

The Complex Hypergeometric function is described by it's author here, and it's application to calculate the Fresnel Integrals is provided on section 3.b with the 41C program example.

I've tested it on my DM41X and it works fine but as mentioned by Jean-Marc Baillard, the input parameter must be small, compared with your example :
S(3.9) = 0.4752 and C(3.9) = 0.4223
it returns S(3.9) = 0.4752 and C(3.9) = 0.4282
and for x>=4 the result is meaningless.