Integrale,winio+ and fortran95

good morning Thanks to LitusSaxonicum and PaulLaidler about your help now my program is running and give very good results WINAPP INCLUDE<windows.ins> DOUBLE PRECISION A,B,somme CHARACTER50 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 REAL FUNCTION TRAP() INTEGER I,N COMMON A,B,somme,N REAL (SELECTED_REAL_KIND(15,307))X,B,A,somme DX=(B-A)/N TRAPE=(F(A)+F(B))/2 X=A DO 10 I=1,N-1 X=X+DX TRAPE=TRAPE+F(X) 10 CONTINUE TRAP=TRAPEDX somme=TRAP CALL window_update@(somme) RETURN END your very truly[/img]

I'm a great believer in adding white space. I put in some code to catch the obvious error cases - there may be more. The TRAP function should be an INTEGER FUNCTION. You don't need to use the variable 'TRAP' in calculating 'somme'.

WINAPP
OPTIONS (INTL)


PROGRAM INTEGRATOR
INCLUDE<windows.ins> 
DOUBLE PRECISION     A,    B,    somme 
CHARACTER*50         s 
COMMON               A,    B,    somme,    N 
INTEGER              i,    w,              N 
EXTERNAL TRAP 

A     = 0.0D0 
B     = 0.0D0 
somme = 0.0D0 
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+1.0D0 
RETURN 
END 


INTEGER FUNCTION TRAP() 
INTEGER             I,          N 
COMMON              A,          B,      somme,     N 
REAL (SELECTED_REAL_KIND(15,307))  X, B, A, somme
INCLUDE <WINDOWS.INS>

IF (A .EQ. B .OR. N .EQ. 0) THEN
    IA=WINIO@('%ca[Error!]%cn%si!%ff%nl%cnCannot integrate this&')
    IA=WINIO@('%2nl%cn%bt[OK]')
    TRAP = 1
    RETURN
    ENDIF 
DX    = (B-A)/N 
TRAPE = (F(A)+F(B))/2.0D0 
X     = A 
DO 10 I=1,N-1 
X     = X + DX 
TRAPE = TRAPE+F(X) 
10 CONTINUE 

somme=TRAPE*DX 

CALL window_update@(somme)
TRAP = 1 
RETURN 
END

Happy New Year

Eddie