Segmentation fault with optional arguments in Fortran functions
fortran, function, optional-parameters
Solution
I found the problem, I used the variable even when not present on the fourth line (in `tol = 1e-6`):
real function foo(x, tol)
real, intent(in) :: x
real, optional, intent(inout) :: tol
if( .not. present(tol) ) tol = 1e-6
!...
end function foo
But I would like to use it even when not present and set a default value, like when in C++ we do something like that
double foo(double x, double tol=1e-6)
Unfortunately, it seems it is not possible in Fortran.
Problem
I can use Fortran optional argumenrs with subroutines with `intent(in)` and `intent(inout)`, but with functions optional arguments work only with `intent(in)`, right? With `intent(inout)` I get segmentation faults in the following code: ``` real function foo(x, tol) real, intent(in) :: x real, optional, intent(inout) :: tol if( .not. present(tol) ) tol = 1e-6 !... end function foo ```