| ESBArcCos Function | 
Unit
QESBPCSMath
Declaration
Function ESBArcCos(const X: Extended): Extended;
Description
Return Values are between 0 and Pi.
| Parameters | 
| X | Float to process. | 
Category
Arithmetic Routines for FloatsImplementation
 
| function ESBArcCos (const X: Extended): Extended;
var
     Y: Extended;
begin
     if abs (X) > 1 then
          raise EMathError.Create (rsValueLEOne);
     if X = 0 then
          Result := PiOn2
     else
     begin
          Y := Sqrt (1 - Sqr (X));
          if FloatIsZero (Y) then
          begin
               if X > 0 then
                    Result := 0
               else
                    Result := ESBPi
          end
          else
               Result := ESBArcTan (X, Y)
     end;
End; | 
|  |