annuity(3M)															       annuity(3M)

NAME

       annuity(), annuityf(), annuityl(), annuityw(), annuityq() - present value factor for annuity

SYNOPSIS

DESCRIPTION

       The function computes the present value factor for an annuity:

	      (1 - (1 + rate) ** (-periods)) / rate

       is a version of it takes arguments and returns a result.

       is a version of it takes arguments and returns a result.

       is an version of it takes arguments and returns an result.

       is equivalent to on HP-UX systems.

USAGE

       To  use	these  functions, compile either with the default option or with the and options.  To use compile with the option.  Make sure your
       program includes Link in the math library by specifying on the compiler or linker command line.

RETURN VALUE

       If periods equals zero, returns 0.0.

       Else, if rate equals zero, returns periods.

       Else, if either argument is a NaN, returns a NaN.

       Else, if rate < -1, returns a NaN and raises the invalid exception.

       Else, if rate = -1 and periods = +INFINITY, returns +INFINITY.

       Else, if rate equals -1 and periods > 0, is equivalent to

       Else, if rate equals -1, returns -1.

       Else, if rate equals +INFINITY and periods >= 0, returns +0.0.

       Else, if rate equals +INFINITY and -1 < periods < 0, returns -0.0.

       Else, if rate equals +INFINITY and periods = -1, returns -1.

       Else, if rate equals +INFINITY, returns -INFINITY.

       Else, if periods is infinite and (rate * periods) > 0, is equivalent to

       Else, if periods is infinite, returns periods.

       returns a properly signed infinity in lieu of a value whose magnitude is too large, and raises the overflow and inexact exceptions.

       raises the underflow and inexact exceptions whenever a result is tiny (essentially denormal or zero) and thereby suffers loss of  accuracy,
       and may raise those exceptions if the result is merely tiny.

ERRORS

       No errors are defined.

SEE ALSO

       compound(3M), exp(3M), expm1(3M), pow(3M), math(5).

STANDARDS CONFORMANCE

       These functions are not specified by any standard.

							     HP Integrity Server Only						       annuity(3M)