[Overview][Constants][Types][Classes][Procedures and functions] Reference for unit 'math' (#rtl)

arctan2

Return arctangent of (y/x)

Declaration

Source position: math.pp line 244

function arctan2(

  y: float;

  x: float

):float;

Description

arctan2calculates arctan(y/x), and returns an angle in the correct quadrant. The returned angle will be in the range $-\pi$ to $\pi$ radians. The values of xand ymust be between -2\^{}64 and 2\^{}64, moreover xshould be different from zero. On Intel systems this function is implemented with the native intel fpataninstruction.

Errors

If xis zero, an overflow error will occur.

See also

arccos

  

Return inverse cosine

arcosh

  

Return inverse hyperbolic cosine

arsinh

  

Return inverse hyperbolic sine

artanh

  

Return inverse hyperbolic tangent

Example

Program Example6;

{ Program to demonstrate the arctan2 function. }

Uses math;

  Procedure WriteRadDeg(X : float);

  begin
    Writeln(X:8:5,' rad = ',radtodeg(x):8:5,' degrees.')
  end;

begin
  WriteRadDeg (arctan2(1,1));
end.