The routines used for the numerical integrations are taken from the book 'Numerical Recipes in C' [5]. The functions used in calc_lib.so are:
- qromb.c
- trapzd.c
- polint.c
- vector.c
- free_vector.c
- nrerror.c
The source code of the routines has been copied into the source code of calc_lib.so and then modified. The data types of the routines has been changed to double instead of float. The prototype declaration of the pointer to the function to be integrated has been changed to accept more arguments and the prototype declaration of the routines themselves has been changed to accept these additional arguments so that they can then be passed on to the function which is to be integrated. The algorithms themselves haven't been changed. Only the integration properties used by qromb.c (fractional accuracy, number of steps,...) has been adjusted to the integrations performed in calc_lib.so. For further information on the C routines listed above, see [5].