Technical details concerning this release
The Simfit package runs in Windows, Linux, and Mac, and uses some 220
procedures for numerical calculations, which are implemented
in two distinct ways.
- The academic version of Simfit
This relies on two dynamic link libraries called
w_maths.dll and w_numbers.dll (x64_maths.dll and x64_numbers.dll
in the 64-bit version) to perform the necessary
calculations. These DLLs either use code written by Bill Bardsley,
or else public domain routines, to implement
the techniques recommended by the Numerical Analysis
Group (NAG). The academic version is completely free and
suitable for student use.
- The NAG library versions of Simfit
These employ alternative versions of w_maths.dll
and w_numbers.dll that are linked directly to the actual
NAG library DLLs, so that the NAG routines can be used
for numerical analysis. These professional versions are also
free, but they can only be used by those having a valid
set of NAG DLLs.
The NAG library versions have increased functionality over the
academic version, and have more facilities in the
areas of optimisation, differential equation solving, curve
fitting, and statistics.
- Swapping between versions
There is only one Simfit installation program called simfit_setup8_a_b.exe
(or x64_simfit_setup8_a_b.exe for the 64-bit version)
but a program called change_simfit_version.exe (or x64_change_simfit_version.exe
for the 64-bit version)
is distributed with the Simfit package and, when Simfit is not running, it can be used
to swap between the Academic and NAG versions of Simfit.
- The Linux version of Simfit
The only difference between the Linux and Simfit versions is in
the first line of the file l_simfit.cfg. The default installation
is for Windows, so first-time Linux users must make sure that
this file is deleted from their Home and Simfit folders before
running Simfit for the first time, so that Simfit can create a
Linux configuration. Linux users must read the file linux.txt
distributed with the Simfit package, and should not attempt
to install the GhostScript or GSview packages, as such utilities
are always built into Linux installations.