Hi!
I recently downloaded the STANMOD software program, and I have started to use it to plot effluent concentrations for the two-region model of transport in porous media. However, I would ideally like to have a little bit more flexibility in regards to what information about the analytical models I can access, so I wondered whether it would be possible to gain direct access to the source code ?
I am especially interested in more details concerning the implementation of the numerical integration routines. As far as I understand it, you are mainly using Romberg and/or Gauss-Chebyshev methods? Not having much experience in this area, I have found it a bit of a stumbling block to evaluate some of the integrals correctly when the limits of integration are either infinity or the integrand is undefined there (typical example: integral from zero to infinity of integrand with 1/x term and lots of trigonometric and hyperbolic functions). If I cannot access the code directly, is there someone who at least elaborate a bit on the techniques used and/or point me to relevant literature?
Also, I downloaded the CXTFIT/Excel tool, but when I tried to open it on my computer I got an error message saying "Could not load some objects, because they are not available on this machine", so the macros don't seem to work correctly. Could this be related to the fact that I use the Excel 2013 version, and if so do you know if there is an easy fix?
I hope these questions are not inappropriate to ask on this forum.
Regards
- Oddbjørn