NAME
    hmean - harmonic mean of a number of values

SYNOPSIS
    hmean(x_1, x_2, ...)

TYPES
    x_1, ...	arithmetic or list

    return	determined by types of arguments, or null

DESCRIPTION
    The null value is returned if there are no arguments.

    If there are n non-list arguments x_1, x_2, ... and the
    required operations are defined, hmean(x_1, x_2, ...) returns the
    value of:

	n/(inverse(x_1) + inverse(x_2) + ... + inverse(x_n)).

    If an argument x_i is a list as defined by list(y_1, ..., y_m)
    this is treated as if in (x_1, x_2, ...), x_i is replaced by
    y_1, ..., y_m.


EXAMPLE
    > c = config("mode", "frac")
    > print hmean(1), hmean(1,2), hmean(1,2,3), hmean(1,2,3,4), hmean(1,2,0,3)
    1 4/3 18/11 48/25 0

LIMITS
    The number of arguments is not to exceed 100.

LIBRARY
    none

SEE ALSO
    avg