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+--- Thread: Passing Arrays? (/thread-8022.html)
Passing Arrays? - toml_12953 - 03-24-2017 03:40 PM
I'm trying to fill an array in a subprogram. I always get back zeros. What am I doing wrong? Are the parameters passed by value only? If so, is there a way to pass them by reference?
TIA
Tom L
Code:
SET_CONIC( COEF, A, B )
BEGIN
COEF(1) := A;
COEF(2) := B;
END;
EXPORT TESTPASS()
BEGIN
LOCAL C:=MAKEMAT(0,2);
SET_CONIC( C, 14, -4 );
PRINT( C );
END;RE: Passing Arrays? - Han - 03-24-2017 03:47 PM
Both C and COEF are local variables, and therefore their context is restricted to only the subprograms that declare them. Variables are passed by value.
Either declare a local variable outside of the context of the subprograms to hold the coefficient values, or modify your subprogram to return the modified coefficients.
For example:
Code:
// set values of conic coefficient array
SET_CONIC( COEF, A, B, C, D, E, F )
BEGIN
COEF(1) := A;
COEF(2) := B;
COEF(3) := C;
COEF(4) := D;
COEF(5) := E;
COEF(6) := F;
RETURN(COEF);
END;
EXPORT TESTPASS()
BEGIN
LOCAL C:=MAKEMAT(0,6);
C:=SET_CONIC( C, 14, -4, 11, -44, -58, 71 );
PRINT( C );
END;or
Code:
COEF:=[0,0,0,0,0,0];
// set values of conic coefficient array
SET_CONIC( A, B, C, D, E, F )
BEGIN
COEF(1) := A;
COEF(2) := B;
COEF(3) := C;
COEF(4) := D;
COEF(5) := E;
COEF(6) := F;
END;
EXPORT TESTPASS()
BEGIN
SET_CONIC( 14, -4, 11, -44, -58, 71 );
PRINT( COEF );
END;RE: Passing Arrays? - toml_12953 - 03-24-2017 05:23 PM
(03-24-2017 03:47 PM)Han Wrote: Both C and COEF are local variables, and therefore their context is restricted to only the subprograms that declare them. Variables are passed by value.
Either declare a local variable outside of the context of the subprograms to hold the coefficient values, or modify your subprogram to return the modified coefficients.
For example:
Code:
// set values of conic coefficient array
SET_CONIC( COEF, A, B, C, D, E, F )
BEGIN
COEF(1) := A;
COEF(2) := B;
COEF(3) := C;
COEF(4) := D;
COEF(5) := E;
COEF(6) := F;
RETURN(COEF);
END;
EXPORT TESTPASS()
BEGIN
LOCAL C:=MAKEMAT(0,6);
C:=SET_CONIC( C, 14, -4, 11, -44, -58, 71 );
PRINT( C );
END;
Thanks! I chose the above method.
Tom L
RE: Passing Arrays? - cyrille de brébisson - 03-28-2017 05:58 AM
Hello,
Variables are always passed by value. Sorry.
Cyrille