NAME
    pi - evaluate pi to specified accuracy

SYNOPSIS
    pi([eps])

TYPES
    eps         0 < real < 1, defaults to epsilon()

    return      real

DESCRIPTION
    Returns a multiple of eps differing from the true value of pi by
    less than 0.75 eps, and in nearly all cases by less than 0.5 eps.

EXAMPLE
    ; print pi(1e-5), pi(1e-10), pi(1e-15), pi(1e-20)
    3.14159 3.1415926536 3.141592653589793 3.14159265358979323846

LIMITS
    0 < eps < 1

LINK LIBRARY
    NUMBER *qpi(NUMBER *eps)

SEE ALSO
    atan2

## Copyright (C) 1999-2006,2023  Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
## or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL.  You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
##
## Under source code control:   1995/10/25 04:03:46
## File existed as early as:    1995
##
## chongo <was here> /\oo/\     http://www.isthe.com/chongo/
## Share and enjoy!  :-)        http://www.isthe.com/chongo/tech/comp/calc/
