gnucash/libgnucash/engine/gnc-numeric.scm
John Ralls e0300d3a62 Replace the gnc:numeric pair with normal Scheme rationals.
This allows direct conversion between Scheme numbers and gnc_numeric
without the performance or accuracy penalties arising from using doubles
as an intermediary.
2017-12-21 15:33:15 -08:00

78 lines
2.9 KiB
Scheme

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; gnc-numeric.scm : rational number representation for gnucash
;; Copyright 2000 Bill Gribble <grib@gnumatic.com>
;; Copyright 2001 Christian Stimming <stimming@tu-harburg.de>
;;
;; This program is free software; you can redistribute it and/or
;; modify it under the terms of the GNU General Public License as
;; published by the Free Software Foundation; either version 2 of
;; the License, or (at your option) any later version.
;;
;; This program 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 General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program; if not, contact:
;;
;; Free Software Foundation Voice: +1-617-542-5942
;; 51 Franklin Street, Fifth Floor Fax: +1-617-542-2652
;; Boston, MA 02110-1301, USA gnu@gnu.org
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; use 'logior' in guile to bit-combine RND and DENOM flags.
(define GNC-RND-FLOOR 1)
(define GNC-RND-CEIL 2)
(define GNC-RND-TRUNC 3)
(define GNC-RND-PROMOTE 4)
(define GNC-RND-ROUND-HALF-DOWN 5)
(define GNC-RND-ROUND-HALF-UP 6)
(define GNC-RND-ROUND 7)
(define GNC-RND-NEVER 8)
(define GNC-DENOM-AUTO 0)
(define GNC-DENOM-REDUCE 32)
(define GNC-DENOM-FIXED 64)
(define GNC-DENOM-LCD 48)
(define GNC-DENOM-SIGFIG 80)
(define (GNC-DENOM-SIGFIGS n)
(logior GNC-DENOM-SIGFIG (* n 256)))
(define GNC-ERROR-OK 0)
(define GNC-ERROR-ARG -1)
(define GNC-ERROR-OVERFLOW -2)
(define GNC-ERROR-DENOM-DIFF -3)
(define GNC-ERROR-REMAINDER -4)
(define <gnc-monetary>
(make-record-type "<gnc-monetary>"
'(commodity amount)))
;; Constructor; takes one <gnc:commodity*> and one <gnc-numeric>
(define (gnc:make-gnc-monetary c a)
;;FIXME: we used to type-check the values, like:
;; (gw:wcp-is-of-type? <gnc:commodity*> c)
(if (and #t (number? a))
((record-constructor <gnc-monetary>) c a)
(warn "wrong arguments for gnc:make-gnc-monetary: " c a)))
(define gnc:gnc-monetary?
(record-predicate <gnc-monetary>))
(define gnc:gnc-monetary-commodity
(record-accessor <gnc-monetary> 'commodity))
(define gnc:gnc-monetary-amount
(record-accessor <gnc-monetary> 'amount))
(define (gnc:monetary-neg a)
(if (gnc:gnc-monetary? a)
(gnc:make-gnc-monetary
(gnc:gnc-monetary-commodity a)
(gnc-numeric-neg (gnc:gnc-monetary-amount a)))
(warn "wrong arguments for gnc:monetary-neg: " a)))