#help_index "Math"

public double Abs(double i)
{
  if (i<0)
    return -i;
  else
    return i;
}

public double Sign(double i)
{
  if (i<0)
    return -1.0;
  else if (!i)
    return 0.0;
  else
    return 1.0;
}

public double Sqr(double d)
{
  return d*d;
}

public void R2P(double *mag,double *arg,double x,double y)
{  //Rect to polar
  *arg=Arg(x,y);
  *mag=Sqrt(x*x+y*y);
}

public void P2R(double *x,double *y,double mag,double arg)
{  //Polar to Rect
  *x=mag*Cos(arg);
  *y=mag*Sin(arg);
}

public double Unwrap(double theta,double base=-pi)
{
  double result=theta%pi2;
  if (result<base)     result+=pi2;
  if (result>base+pi2) result-=pi2;
  return result;
}

public I8 SignI8(I8 i)
{
  if (i<0)
    return -1;
  else if (!i)
    return 0;
  else
    return 1;
}

public I8 SqrI8(I8 i)
{
  return i*i;
}

public I8 DistI8(I8 x1,I8 y1,I8 x2,I8 y2)
{
  I8 dx=x1-x2,dy=y1-y2;
  return dx*dx+dy*dy;
}
#help_index ""