Problem with NaN

Bob_G_ · ‎04-12-2013

Program Main
...
do loop=1,n
call test1(...)
enddo
end Program Main
subroutine test1(...)
a=sin(2)
b=cos(2)
end subroutine test1

Here is the problem, when loop=1, both a and b got the correct value, while loop>=2, only b is correctly calculated and a=NaN. I can figure out what is the problem. Also I tried different codes, they both showed that only the frist expressioin with fortran internal function goes wrong. How to fix it..

Steven_L_Intel1 · ‎04-12-2013

Please show us an actual and complete source that shows the problem. My experience is that paraphrases and snippets almost always omit key information.

Is test1 actually a subroutine or is it a function? If you are calling a function as a subroutine (or vice versa) you can end up with symptoms like this. Generated interface checking usually detects this.