DLAPY2 (3lapack)

return sqrt(x**2+y**2), taking care not to cause unnecessary overflow

SYNOPSIS

  DOUBLE PRECISION FUNCTION DLAPY2( X, Y )

      DOUBLE       PRECISION X, Y

PURPOSE

  DLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary
  overflow.

ARGUMENTS

  X       (input) DOUBLE PRECISION
          Y       (input) DOUBLE PRECISION X and Y specify the values x and
          y.