1st program with problems "Euler Method"

[oneletterz]

whats wrong with this?

Code:


EXPORT eulerm(funct,X0,Y0,ch,times)
BEGIN
LOCAL a, s,check,x,y,myfunct;
myfunct:=EXPR(funct);
RETURN(myfunct(x,y));
MAKEMAT(0,times,2)▶s;
check=0;
FOR a FROM 0 TO times DO
IF check==0 THEN
s(a,0):=X0;
s(a,1):=Y0;
check:=1;
ELSE
s(a,0):=s(a-1,0)+ch;
x:=s(a,0);
y:=s(a-1,1);
s(a,1):=y+(myfunct)*ch; 
END;

END;

END;