/******************************************************************** * gnc-numeric.h -- an exact-number library for gnucash. * * Copyright (C) 2000 Bill Gribble * * * * 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 * * 59 Temple Place - Suite 330 Fax: +1-617-542-2652 * * Boston, MA 02111-1307, USA gnu@gnu.org * * * *******************************************************************/ #ifndef GNC_NUMERIC_H #define GNC_NUMERIC_H #include struct _gnc_numeric { gint64 num; gint64 denom; }; typedef struct _gnc_numeric gnc_numeric; /* bitmasks for HOW flags */ #define GNC_NUMERIC_RND_MASK 0x0000000f #define GNC_NUMERIC_DENOM_MASK 0x000000f0 #define GNC_NUMERIC_SIGFIGS_MASK 0x0000ff00 /* rounding/truncation modes for operations */ enum { GNC_RND_FLOOR = 0x01, GNC_RND_CEIL = 0x02, GNC_RND_TRUNC = 0x03, GNC_RND_PROMOTE = 0x04, GNC_RND_ROUND_HALF_DOWN = 0x05, GNC_RND_ROUND_HALF_UP = 0x06, GNC_RND_ROUND = 0x07, GNC_RND_NEVER = 0x08 }; /* auto-denominator types */ enum { GNC_DENOM_EXACT = 0x10, GNC_DENOM_REDUCE = 0x20, GNC_DENOM_LCD = 0x30, GNC_DENOM_FIXED = 0x40, GNC_DENOM_SIGFIG = 0x50 }; /* bits 8-15 of 'how' are reserved for the number of significant * digits to use in the output with GNC_DENOM_SIGFIG */ /* errors */ enum { GNC_ERROR_OK = 0, GNC_ERROR_ARG = -1, GNC_ERROR_OVERFLOW = -2, GNC_ERROR_DENOM_DIFF = -3, GNC_ERROR_REMAINDER = -4 }; #define GNC_DENOM_AUTO 0 #define GNC_DENOM_RECIPROCAL( a ) (- ( a )) #define GNC_DENOM_SIGFIGS( a ) ( ((( a ) & 0xff) << 8) | GNC_DENOM_SIGFIG) #define GNC_NUMERIC_GET_SIGFIGS( a ) ( (( a ) & 0xff00 ) >> 8) /* make a gnc_numeric from numerator and denominator */ gnc_numeric gnc_numeric_create(gint64 num, gint64 denom); /* create a zero-value gnc_numeric */ gnc_numeric gnc_numeric_zero(void); /* make a special error-signalling gnc_numeric */ gnc_numeric gnc_numeric_error(int error_code); /* check for error signal in value */ int gnc_numeric_check(gnc_numeric a); /* get parts */ gint64 gnc_numeric_num(gnc_numeric a); gint64 gnc_numeric_denom(gnc_numeric a); /* tests */ int gnc_numeric_zero_p(gnc_numeric a); /* 1 if 0, 0 else */ int gnc_numeric_compare(gnc_numeric a, gnc_numeric b); int gnc_numeric_negative_p(gnc_numeric a); int gnc_numeric_positive_p(gnc_numeric a); /* equivalence predicates : * eq : a and b are exactly the same (same numerator and denominator) * equal : a and b represent exactly the same number (ratio of numerator * to denominator is exactly equal) * same : after both are converted to DENOM using method HOW, a and b * are equal(). */ int gnc_numeric_eq(gnc_numeric a, gnc_numeric b); int gnc_numeric_equal(gnc_numeric a, gnc_numeric b); int gnc_numeric_same(gnc_numeric a, gnc_numeric b, gint64 denom, gint how); /* arithmetic operations */ gnc_numeric gnc_numeric_add(gnc_numeric a, gnc_numeric b, gint64 denom, gint how); gnc_numeric gnc_numeric_sub(gnc_numeric a, gnc_numeric b, gint64 denom, gint how); gnc_numeric gnc_numeric_mul(gnc_numeric a, gnc_numeric b, gint64 denom, gint how); gnc_numeric gnc_numeric_div(gnc_numeric a, gnc_numeric b, gint64 denom, gint how); gnc_numeric gnc_numeric_neg(gnc_numeric a); gnc_numeric gnc_numeric_abs(gnc_numeric a); /* some shortcuts for common operations */ gnc_numeric gnc_numeric_add_fixed(gnc_numeric a, gnc_numeric b); gnc_numeric gnc_numeric_sub_fixed(gnc_numeric a, gnc_numeric b); /* arithmetic functions with exact error returns */ gnc_numeric gnc_numeric_add_with_error(gnc_numeric a, gnc_numeric b, gint64 denom, gint how, gnc_numeric * error); gnc_numeric gnc_numeric_sub_with_error(gnc_numeric a, gnc_numeric b, gint64 denom, gint how, gnc_numeric * error); gnc_numeric gnc_numeric_mul_with_error(gnc_numeric a, gnc_numeric b, gint64 denom, gint how, gnc_numeric * error); gnc_numeric gnc_numeric_div_with_error(gnc_numeric a, gnc_numeric b, gint64 denom, gint how, gnc_numeric * error); /* change the denominator of a gnc_numeric value */ gnc_numeric gnc_numeric_convert(gnc_numeric in, gint64 denom, gint how); gnc_numeric gnc_numeric_convert_with_error(gnc_numeric in, gint64 denom, gint how, gnc_numeric * error); /* reduce by GCF elimination */ gnc_numeric gnc_numeric_reduce(gnc_numeric in); /* convert to and from floating-point values */ gnc_numeric double_to_gnc_numeric(double in, gint64 denom, gint how); double gnc_numeric_to_double(gnc_numeric in); gchar *gnc_numeric_to_string(gnc_numeric n); /* Read a gnc_numeric from str, skipping any leading whitespace, and returning a pointer to just past the last byte read. Return NULL on error. */ const gchar *string_to_gnc_numeric(const gchar* str, gnc_numeric *n); #endif