Calcul an integrale with winio+and fortran95

Good morning I thank LitusSaxonicum for his help to do my program Now i have this program WINAPP INCLUDE<windows.ins> DOUBLE PRECISION A,B,somme CHARACTER*50 s COMMON A,B,somme,N INTEGER i,w,N EXTERNAL TRAP A=0.0E0 B=0.0E0 somme=0.0E0 N=0 i=winio@('%ca[Calcule une integrale]&') s='{integral A;B} (X+1)dx=somme' w=winio@('%ob%eq@%cb&',s,0,0) w=winio@('&') i=winio@('%5tl&',1,2,3,4,5) i=winio@('%ffA=%ta&') i=winio@('%rf&',A) i=winio@('%ffB=%ta&') i=winio@('%rf&',B) i=winio@('%ffsomme=%ta&') i=winio@('%rf&',somme) i=winio@('%ffN=%ta&') i=winio@('%rd&',N) i=winio@('%ta%`^12bt[INTEGRATION]',TRAP) END

FUNCTION F(T) REAL(SELECTED_REAL_KIND(15,307))T

F=T+1 RETURN END INTEGER FUNCTION TRAP()

INTEGER I,N COMMON A,B,somme,N REAL (SELECTED_REAL_KIND(15,307))X,B,A,somme

DX=(B-A)/N TRAP=(F(A)+F(B))/2 X=A DO 10 I=1,N-1 X=X+DX TRAP=TRAP+F(X) 10 CONTINUE TRAP=TRAP*DX somme=TRAP CALL window_update@(somme) RETURN END The program is running and gives results I have run many examples but results are always lower than the right result With the example i send you the result is 175 for 181.5 Your very truly

Part of the problem is that TRAP is declared as INTEGER when it should be REAL.

To amplify Paul's comments: your use of Integer function TRAP in a callback is OK, but it should return integer 1 or 0. In that function, you should not be using the variable TRAP as if it was a general purpose real variable - use something else. In fact as a general rule I make my callback function names something I wouldn't accidentally use as anything else.

Glad to have helped the previous time.

Eddie