The problem is to calculate the array of functions f(x) defined as:
see Figure1
and then
see Figure2
Some coefficients of the matrix “A” are in the form:
see Figure3
For this reason, for large values “x” the matrix “A” becomes singular and the linear system bad conditioned.
Anyway, in double precision if “x > 706” the calculation of the coefficient gives underflow.
Matrix preconditioning seems not effective.
Are there math trick to overcome the problem?
