System Functions
ACS( ) Return Arc-Cosine
 
Format ACS(num[,ERR=stmtref])
 
Where:
 
num Numeric expression (range: -1 to +1) whose Arc-Cosine is to be returned.
 
stmtref Program line number or statement label to which to transfer control.
 
Returns Numeric value between 0 (zero) and ð (pi=3.14159...)
 
Description The ACS( ) function returns the Arc-Cosine of the numeric expression num. It returns a value between 0 (zero) and ð (pi) rounded to the current PRECISION in effect. This is the inverse of the COS( ) function.
 
The value of your numeric must be in the range of -1 to +1 inclusive. Otherwise
ProvideX returns
 
Error #40: Divide check or numeric overflow.
 
Examples 0060 FOR I=-1 TO 1 STEP .1
0070 PRINT ACS(I),
0080 NEXT
0090 PRINT " DONE"
0100 END
-:run
3.14 2.69 2.5 2.35 2.21 2.09 1.98 1.88 1.77 1.67 1.57 1.47 1.37 1.27 1.16
1.05 0.93 0.8 0.64 0.45 0 DONE