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[kingkastle]

Hi,

I found a problem that drive me crazy and i can´t find the way to short it out, here it is:

I created an IF statment and I would like to use .AND. into the logical statment as I show below:
DO i = 1, siz
Diff(i)= Frct(i) - Obs(i)
IF (ABS(Diff(i)) <= Threshold) THEN
x(1)=x(1)+1

ELSE IF (Diff(i) > Threshold) THEN
x(2)=x(2)+1

ELSE IF (Diff(i) < -Threshold) THEN
x(3)=x(3)+1

ELSE IF (ABS(Diff(i)) <= Threshold .AND. ABS(Frct(i)) <= Threshold) THEN !NO ESTA CORRECTO, I should think about
x(4)=x(4)+1

END IF
END DO


The point is: the program just forgets thte statmentment that is after .AND.
My question is: How could I write the statment to match all statments???
Thaqnks in advance

[brucebowler]

Because of the first if, the last else if will never be executed (nor will the intervening else if's for that matter)

[kingkastle]

Sorry, but it´s still not clear to me......, would you mind an expanded explanation???
thanks

[brucebowler]

Consider the case where abs(diff(i)) <= threshold.

In that case, x(1) will be incremented by 1 and control will transfer to the next statement after the endif and NONE of the else statements will be executed.

Depending on what it is you want to do, you might try something like

[kingkastle]

Thanks I got it!!!,

I understood what you was saying in the first post: In the way it was wrote, the last condition will never be executed.
I re-wrote the code and now is working perfectly, here it is:

DO i = 1, siz
Diff(i)= Frct(i) - Obs(i)
IF (ABS(Diff(i)) <= Threshold .AND. ABS(Frct(i)) <= Threshold) THEN
x(4)=x(4)+1

ELSE IF (Diff(i) > Threshold) THEN
x(2)=x(2)+1

ELSE IF (Diff(i) < -Threshold) THEN
x(3)=x(3)+1

ELSE IF (ABS(Diff(i)) <= Threshold) THEN
x(1)=x(1)+1

END IF
END DO
Thanks very much