SIS function blocks > SIS Math Blocks > Logic Solver Calculation function block > Expressions in DeltaV SIS Software > Functions in Logic Solver Expressions

ACOS function

Arccosine of x. ACOS (x) returns the arccosine of x in the range 0 to pi radians. When x is less than -1 or greater than 1, ACOS returns a zero value and BAD status.

Syntax:

'external reference' := ACOS(Real value);

Example:

VAR     
   T63; T64; T17; T18; (* Temporary values *)
END_VAR;
T63 := .5;
T64 := -.5;
T17 := ACOS(T63);
T18 := ACOS(T64);

The above example shows T63 set to the value of .5 and T64 set to the value of .5. T17 is set to the result of ACOS(T63), which is 1.047197551197 and T18 is set to the result of ACOS(T64), which is 2.094395102393.