pow() raises a floating-point base x to a floating-point exponent
    y. The value of pow(x,y) is computed as e**(y ln(x)) for positive
    x. If x is 0 or negative, see your language reference manual.

    Passing a NaN input value to pow() produces a NaN result for
    nonzero values of y. For pow(NaN,0), see your language reference
    manual.

                           Entry-Point Names

    Generic
    Function   Data Type   OpenVMS        Tru64 UNIX
    Name       Required

    pow        S_FLOAT     math$pow_ss    powf
               T_FLOAT     math$pow_tt    pow
               X_FLOAT     math$pow_xx    powl
               F_FLOAT     math$pow_ff
               G_FLOAT     math$pow_gg