freepascal.compiler/tests/test/units/system/ttrig.pas

procedure do_error(i : longint);
  begin
    writeln('Error near ',i);
    halt(1);
  end;

var
  s0,s1,s2 : single;


begin
  writeln('--- Testing single functions ---');

  // 0.0
  s0:=0.0;

  s1:=sin(s0);
  if s1<>0.0 then
    do_error(1);

  s1:=cos(s0);
  if s1<>1.0 then
    do_error(2);

  s1:=arctan(s0);
  if s1<>0.0 then
    do_error(3);

  // pi/2
  s2:=pi/2;

  s1:=sin(s2);
  if s1<>1.0 then
    do_error(100);

  s1:=cos(s2);
  { with single precision, the result is -4.371138829E-08 }
  if abs(s1-0.0)>4.371138829E-08 then
    do_error(101);
end.