ruby/rational.c

2146 строки
44 KiB
C

/*
rational.c: Coded by Tadayoshi Funaba 2008,2009
This implementation is based on Keiju Ishitsuka's Rational library
which is written in ruby.
*/
#include "ruby.h"
#include <math.h>
#include <float.h>
#ifdef HAVE_IEEEFP_H
#include <ieeefp.h>
#endif
#define NDEBUG
#include <assert.h>
#define ZERO INT2FIX(0)
#define ONE INT2FIX(1)
#define TWO INT2FIX(2)
VALUE rb_cRational;
static ID id_abs, id_cmp, id_convert, id_eqeq_p, id_expt, id_fdiv,
id_floor, id_idiv, id_inspect, id_integer_p, id_negate, id_to_f,
id_to_i, id_to_s, id_truncate;
#define f_boolcast(x) ((x) ? Qtrue : Qfalse)
#define binop(n,op) \
inline static VALUE \
f_##n(VALUE x, VALUE y)\
{\
return rb_funcall(x, op, 1, y);\
}
#define fun1(n) \
inline static VALUE \
f_##n(VALUE x)\
{\
return rb_funcall(x, id_##n, 0);\
}
#define fun2(n) \
inline static VALUE \
f_##n(VALUE x, VALUE y)\
{\
return rb_funcall(x, id_##n, 1, y);\
}
inline static VALUE
f_add(VALUE x, VALUE y)
{
if (FIXNUM_P(y) && FIX2LONG(y) == 0)
return x;
else if (FIXNUM_P(x) && FIX2LONG(x) == 0)
return y;
return rb_funcall(x, '+', 1, y);
}
inline static VALUE
f_cmp(VALUE x, VALUE y)
{
if (FIXNUM_P(x) && FIXNUM_P(y)) {
long c = FIX2LONG(x) - FIX2LONG(y);
if (c > 0)
c = 1;
else if (c < 0)
c = -1;
return INT2FIX(c);
}
return rb_funcall(x, id_cmp, 1, y);
}
inline static VALUE
f_div(VALUE x, VALUE y)
{
if (FIXNUM_P(y) && FIX2LONG(y) == 1)
return x;
return rb_funcall(x, '/', 1, y);
}
inline static VALUE
f_gt_p(VALUE x, VALUE y)
{
if (FIXNUM_P(x) && FIXNUM_P(y))
return f_boolcast(FIX2LONG(x) > FIX2LONG(y));
return rb_funcall(x, '>', 1, y);
}
inline static VALUE
f_lt_p(VALUE x, VALUE y)
{
if (FIXNUM_P(x) && FIXNUM_P(y))
return f_boolcast(FIX2LONG(x) < FIX2LONG(y));
return rb_funcall(x, '<', 1, y);
}
binop(mod, '%')
inline static VALUE
f_mul(VALUE x, VALUE y)
{
if (FIXNUM_P(y)) {
long iy = FIX2LONG(y);
if (iy == 0) {
if (FIXNUM_P(x) || TYPE(x) == T_BIGNUM)
return ZERO;
}
else if (iy == 1)
return x;
}
else if (FIXNUM_P(x)) {
long ix = FIX2LONG(x);
if (ix == 0) {
if (FIXNUM_P(y) || TYPE(y) == T_BIGNUM)
return ZERO;
}
else if (ix == 1)
return y;
}
return rb_funcall(x, '*', 1, y);
}
inline static VALUE
f_sub(VALUE x, VALUE y)
{
if (FIXNUM_P(y) && FIX2LONG(y) == 0)
return x;
return rb_funcall(x, '-', 1, y);
}
fun1(abs)
fun1(floor)
fun1(inspect)
fun1(integer_p)
fun1(negate)
fun1(to_f)
fun1(to_i)
fun1(to_s)
fun1(truncate)
inline static VALUE
f_eqeq_p(VALUE x, VALUE y)
{
if (FIXNUM_P(x) && FIXNUM_P(y))
return f_boolcast(FIX2LONG(x) == FIX2LONG(y));
return rb_funcall(x, id_eqeq_p, 1, y);
}
fun2(expt)
fun2(fdiv)
fun2(idiv)
inline static VALUE
f_negative_p(VALUE x)
{
if (FIXNUM_P(x))
return f_boolcast(FIX2LONG(x) < 0);
return rb_funcall(x, '<', 1, ZERO);
}
#define f_positive_p(x) (!f_negative_p(x))
inline static VALUE
f_zero_p(VALUE x)
{
switch (TYPE(x)) {
case T_FIXNUM:
return f_boolcast(FIX2LONG(x) == 0);
case T_BIGNUM:
return Qfalse;
case T_RATIONAL:
{
VALUE num = RRATIONAL(x)->num;
return f_boolcast(FIXNUM_P(num) && FIX2LONG(num) == 0);
}
}
return rb_funcall(x, id_eqeq_p, 1, ZERO);
}
#define f_nonzero_p(x) (!f_zero_p(x))
inline static VALUE
f_one_p(VALUE x)
{
switch (TYPE(x)) {
case T_FIXNUM:
return f_boolcast(FIX2LONG(x) == 1);
case T_BIGNUM:
return Qfalse;
case T_RATIONAL:
{
VALUE num = RRATIONAL(x)->num;
VALUE den = RRATIONAL(x)->den;
return f_boolcast(FIXNUM_P(num) && FIX2LONG(num) == 1 &&
FIXNUM_P(den) && FIX2LONG(den) == 1);
}
}
return rb_funcall(x, id_eqeq_p, 1, ONE);
}
inline static VALUE
f_kind_of_p(VALUE x, VALUE c)
{
return rb_obj_is_kind_of(x, c);
}
inline static VALUE
k_numeric_p(VALUE x)
{
return f_kind_of_p(x, rb_cNumeric);
}
inline static VALUE
k_integer_p(VALUE x)
{
return f_kind_of_p(x, rb_cInteger);
}
inline static VALUE
k_float_p(VALUE x)
{
return f_kind_of_p(x, rb_cFloat);
}
inline static VALUE
k_rational_p(VALUE x)
{
return f_kind_of_p(x, rb_cRational);
}
#define k_exact_p(x) (!k_float_p(x))
#define k_inexact_p(x) k_float_p(x)
#define k_exact_zero_p(x) (k_exact_p(x) && f_zero_p(x))
#define k_exact_one_p(x) (k_exact_p(x) && f_one_p(x))
#ifndef NDEBUG
#define f_gcd f_gcd_orig
#endif
inline static long
i_gcd(long x, long y)
{
if (x < 0)
x = -x;
if (y < 0)
y = -y;
if (x == 0)
return y;
if (y == 0)
return x;
while (x > 0) {
long t = x;
x = y % x;
y = t;
}
return y;
}
inline static VALUE
f_gcd(VALUE x, VALUE y)
{
VALUE z;
if (FIXNUM_P(x) && FIXNUM_P(y))
return LONG2NUM(i_gcd(FIX2LONG(x), FIX2LONG(y)));
if (f_negative_p(x))
x = f_negate(x);
if (f_negative_p(y))
y = f_negate(y);
if (f_zero_p(x))
return y;
if (f_zero_p(y))
return x;
for (;;) {
if (FIXNUM_P(x)) {
if (FIX2LONG(x) == 0)
return y;
if (FIXNUM_P(y))
return LONG2NUM(i_gcd(FIX2LONG(x), FIX2LONG(y)));
}
z = x;
x = f_mod(y, x);
y = z;
}
/* NOTREACHED */
}
#ifndef NDEBUG
#undef f_gcd
inline static VALUE
f_gcd(VALUE x, VALUE y)
{
VALUE r = f_gcd_orig(x, y);
if (f_nonzero_p(r)) {
assert(f_zero_p(f_mod(x, r)));
assert(f_zero_p(f_mod(y, r)));
}
return r;
}
#endif
inline static VALUE
f_lcm(VALUE x, VALUE y)
{
if (f_zero_p(x) || f_zero_p(y))
return ZERO;
return f_abs(f_mul(f_div(x, f_gcd(x, y)), y));
}
#define get_dat1(x) \
struct RRational *dat;\
dat = ((struct RRational *)(x))
#define get_dat2(x,y) \
struct RRational *adat, *bdat;\
adat = ((struct RRational *)(x));\
bdat = ((struct RRational *)(y))
inline static VALUE
nurat_s_new_internal(VALUE klass, VALUE num, VALUE den)
{
NEWOBJ(obj, struct RRational);
OBJSETUP(obj, klass, T_RATIONAL);
obj->num = num;
obj->den = den;
return (VALUE)obj;
}
static VALUE
nurat_s_alloc(VALUE klass)
{
return nurat_s_new_internal(klass, ZERO, ONE);
}
#define rb_raise_zerodiv() rb_raise(rb_eZeroDivError, "divided by 0")
#if 0
static VALUE
nurat_s_new_bang(int argc, VALUE *argv, VALUE klass)
{
VALUE num, den;
switch (rb_scan_args(argc, argv, "11", &num, &den)) {
case 1:
if (!k_integer_p(num))
num = f_to_i(num);
den = ONE;
break;
default:
if (!k_integer_p(num))
num = f_to_i(num);
if (!k_integer_p(den))
den = f_to_i(den);
switch (FIX2INT(f_cmp(den, ZERO))) {
case -1:
num = f_negate(num);
den = f_negate(den);
break;
case 0:
rb_raise_zerodiv();
break;
}
break;
}
return nurat_s_new_internal(klass, num, den);
}
#endif
inline static VALUE
f_rational_new_bang1(VALUE klass, VALUE x)
{
return nurat_s_new_internal(klass, x, ONE);
}
inline static VALUE
f_rational_new_bang2(VALUE klass, VALUE x, VALUE y)
{
assert(f_positive_p(y));
assert(f_nonzero_p(y));
return nurat_s_new_internal(klass, x, y);
}
#ifdef CANONICALIZATION_FOR_MATHN
#define CANON
#endif
#ifdef CANON
static int canonicalization = 0;
void
nurat_canonicalization(int f)
{
canonicalization = f;
}
#endif
inline static void
nurat_int_check(VALUE num)
{
switch (TYPE(num)) {
case T_FIXNUM:
case T_BIGNUM:
break;
default:
if (!k_numeric_p(num) || !f_integer_p(num))
rb_raise(rb_eArgError, "not an integer");
}
}
inline static VALUE
nurat_int_value(VALUE num)
{
nurat_int_check(num);
if (!k_integer_p(num))
num = f_to_i(num);
return num;
}
inline static VALUE
nurat_s_canonicalize_internal(VALUE klass, VALUE num, VALUE den)
{
VALUE gcd;
switch (FIX2INT(f_cmp(den, ZERO))) {
case -1:
num = f_negate(num);
den = f_negate(den);
break;
case 0:
rb_raise_zerodiv();
break;
}
gcd = f_gcd(num, den);
num = f_idiv(num, gcd);
den = f_idiv(den, gcd);
#ifdef CANON
if (f_one_p(den) && canonicalization)
return num;
#endif
return nurat_s_new_internal(klass, num, den);
}
inline static VALUE
nurat_s_canonicalize_internal_no_reduce(VALUE klass, VALUE num, VALUE den)
{
switch (FIX2INT(f_cmp(den, ZERO))) {
case -1:
num = f_negate(num);
den = f_negate(den);
break;
case 0:
rb_raise_zerodiv();
break;
}
#ifdef CANON
if (f_one_p(den) && canonicalization)
return num;
#endif
return nurat_s_new_internal(klass, num, den);
}
static VALUE
nurat_s_new(int argc, VALUE *argv, VALUE klass)
{
VALUE num, den;
switch (rb_scan_args(argc, argv, "11", &num, &den)) {
case 1:
num = nurat_int_value(num);
den = ONE;
break;
default:
num = nurat_int_value(num);
den = nurat_int_value(den);
break;
}
return nurat_s_canonicalize_internal(klass, num, den);
}
inline static VALUE
f_rational_new1(VALUE klass, VALUE x)
{
assert(!k_rational_p(x));
return nurat_s_canonicalize_internal(klass, x, ONE);
}
inline static VALUE
f_rational_new2(VALUE klass, VALUE x, VALUE y)
{
assert(!k_rational_p(x));
assert(!k_rational_p(y));
return nurat_s_canonicalize_internal(klass, x, y);
}
inline static VALUE
f_rational_new_no_reduce1(VALUE klass, VALUE x)
{
assert(!k_rational_p(x));
return nurat_s_canonicalize_internal_no_reduce(klass, x, ONE);
}
inline static VALUE
f_rational_new_no_reduce2(VALUE klass, VALUE x, VALUE y)
{
assert(!k_rational_p(x));
assert(!k_rational_p(y));
return nurat_s_canonicalize_internal_no_reduce(klass, x, y);
}
/*
* call-seq:
* Rational(x[, y]) -> numeric
*
* Returns x/y;
*/
static VALUE
nurat_f_rational(int argc, VALUE *argv, VALUE klass)
{
return rb_funcall2(rb_cRational, id_convert, argc, argv);
}
/*
* call-seq:
* rat.numerator -> integer
*
* Returns the numerator.
*
* For example:
*
* Rational(7).numerator #=> 7
* Rational(7, 1).numerator #=> 7
* Rational(9, -4).numerator #=> -9
* Rational(-2, -10).numerator #=> 1
*/
static VALUE
nurat_numerator(VALUE self)
{
get_dat1(self);
return dat->num;
}
/*
* call-seq:
* rat.denominator -> integer
*
* Returns the denominator (always positive).
*
* For example:
*
* Rational(7).denominator #=> 1
* Rational(7, 1).denominator #=> 1
* Rational(9, -4).denominator #=> 4
* Rational(-2, -10).denominator #=> 5
* rat.numerator.gcd(rat.denominator) #=> 1
*/
static VALUE
nurat_denominator(VALUE self)
{
get_dat1(self);
return dat->den;
}
#ifndef NDEBUG
#define f_imul f_imul_orig
#endif
inline static VALUE
f_imul(long a, long b)
{
VALUE r;
long c;
if (a == 0 || b == 0)
return ZERO;
else if (a == 1)
return LONG2NUM(b);
else if (b == 1)
return LONG2NUM(a);
c = a * b;
r = LONG2NUM(c);
if (NUM2LONG(r) != c || (c / a) != b)
r = rb_big_mul(rb_int2big(a), rb_int2big(b));
return r;
}
#ifndef NDEBUG
#undef f_imul
inline static VALUE
f_imul(long x, long y)
{
VALUE r = f_imul_orig(x, y);
assert(f_eqeq_p(r, f_mul(LONG2NUM(x), LONG2NUM(y))));
return r;
}
#endif
inline static VALUE
f_addsub(VALUE self, VALUE anum, VALUE aden, VALUE bnum, VALUE bden, int k)
{
VALUE num, den;
if (FIXNUM_P(anum) && FIXNUM_P(aden) &&
FIXNUM_P(bnum) && FIXNUM_P(bden)) {
long an = FIX2LONG(anum);
long ad = FIX2LONG(aden);
long bn = FIX2LONG(bnum);
long bd = FIX2LONG(bden);
long ig = i_gcd(ad, bd);
VALUE g = LONG2NUM(ig);
VALUE a = f_imul(an, bd / ig);
VALUE b = f_imul(bn, ad / ig);
VALUE c;
if (k == '+')
c = f_add(a, b);
else
c = f_sub(a, b);
b = f_idiv(aden, g);
g = f_gcd(c, g);
num = f_idiv(c, g);
a = f_idiv(bden, g);
den = f_mul(a, b);
}
else {
VALUE g = f_gcd(aden, bden);
VALUE a = f_mul(anum, f_idiv(bden, g));
VALUE b = f_mul(bnum, f_idiv(aden, g));
VALUE c;
if (k == '+')
c = f_add(a, b);
else
c = f_sub(a, b);
b = f_idiv(aden, g);
g = f_gcd(c, g);
num = f_idiv(c, g);
a = f_idiv(bden, g);
den = f_mul(a, b);
}
return f_rational_new_no_reduce2(CLASS_OF(self), num, den);
}
/*
* call-seq:
* rat + numeric -> numeric_result
*
* Performs addition.
*
* For example:
*
* Rational(2, 3) + Rational(2, 3) #=> (4/3)
* Rational(900) + Rational(1) #=> (900/1)
* Rational(-2, 9) + Rational(-9, 2) #=> (-85/18)
* Rational(9, 8) + 4 #=> (41/8)
* Rational(20, 9) + 9.8 #=> 12.022222222222222
*/
static VALUE
nurat_add(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
{
get_dat1(self);
return f_addsub(self,
dat->num, dat->den,
other, ONE, '+');
}
case T_FLOAT:
return f_add(f_to_f(self), other);
case T_RATIONAL:
{
get_dat2(self, other);
return f_addsub(self,
adat->num, adat->den,
bdat->num, bdat->den, '+');
}
default:
return rb_num_coerce_bin(self, other, '+');
}
}
/*
* call-seq:
* rat - numeric -> numeric_result
*
* Performs subtraction.
*
* For example:
*
* Rational(2, 3) - Rational(2, 3) #=> (0/1)
* Rational(900) - Rational(1) #=> (899/1)
* Rational(-2, 9) - Rational(-9, 2) #=> (77/18)
* Rational(9, 8) - 4 #=> (23/8)
* Rational(20, 9) - 9.8 #=> -7.577777777777778
*/
static VALUE
nurat_sub(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
{
get_dat1(self);
return f_addsub(self,
dat->num, dat->den,
other, ONE, '-');
}
case T_FLOAT:
return f_sub(f_to_f(self), other);
case T_RATIONAL:
{
get_dat2(self, other);
return f_addsub(self,
adat->num, adat->den,
bdat->num, bdat->den, '-');
}
default:
return rb_num_coerce_bin(self, other, '-');
}
}
inline static VALUE
f_muldiv(VALUE self, VALUE anum, VALUE aden, VALUE bnum, VALUE bden, int k)
{
VALUE num, den;
if (k == '/') {
VALUE t;
if (f_negative_p(bnum)) {
anum = f_negate(anum);
bnum = f_negate(bnum);
}
t = bnum;
bnum = bden;
bden = t;
}
if (FIXNUM_P(anum) && FIXNUM_P(aden) &&
FIXNUM_P(bnum) && FIXNUM_P(bden)) {
long an = FIX2LONG(anum);
long ad = FIX2LONG(aden);
long bn = FIX2LONG(bnum);
long bd = FIX2LONG(bden);
long g1 = i_gcd(an, bd);
long g2 = i_gcd(ad, bn);
num = f_imul(an / g1, bn / g2);
den = f_imul(ad / g2, bd / g1);
}
else {
VALUE g1 = f_gcd(anum, bden);
VALUE g2 = f_gcd(aden, bnum);
num = f_mul(f_idiv(anum, g1), f_idiv(bnum, g2));
den = f_mul(f_idiv(aden, g2), f_idiv(bden, g1));
}
return f_rational_new_no_reduce2(CLASS_OF(self), num, den);
}
/*
* call-seq:
* rat * numeric -> numeric_result
*
* Performs multiplication.
*
* For example:
*
* Rational(2, 3) * Rational(2, 3) #=> (4/9)
* Rational(900) * Rational(1) #=> (900/1)
* Rational(-2, 9) * Rational(-9, 2) #=> (1/1)
* Rational(9, 8) * 4 #=> (9/2)
* Rational(20, 9) * 9.8 #=> 21.77777777777778
*/
static VALUE
nurat_mul(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
{
get_dat1(self);
return f_muldiv(self,
dat->num, dat->den,
other, ONE, '*');
}
case T_FLOAT:
return f_mul(f_to_f(self), other);
case T_RATIONAL:
{
get_dat2(self, other);
return f_muldiv(self,
adat->num, adat->den,
bdat->num, bdat->den, '*');
}
default:
return rb_num_coerce_bin(self, other, '*');
}
}
/*
* call-seq:
* rat / numeric -> numeric_result
* rat.quo(numeric) -> numeric_result
*
* Performs division.
*
* For example:
*
* Rational(2, 3) / Rational(2, 3) #=> (1/1)
* Rational(900) / Rational(1) #=> (900/1)
* Rational(-2, 9) / Rational(-9, 2) #=> (4/81)
* Rational(9, 8) / 4 #=> (9/32)
* Rational(20, 9) / 9.8 #=> 0.22675736961451246
*/
static VALUE
nurat_div(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
if (f_zero_p(other))
rb_raise_zerodiv();
{
get_dat1(self);
return f_muldiv(self,
dat->num, dat->den,
other, ONE, '/');
}
case T_FLOAT:
return rb_funcall(f_to_f(self), '/', 1, other);
case T_RATIONAL:
if (f_zero_p(other))
rb_raise_zerodiv();
{
get_dat2(self, other);
if (f_one_p(self))
return f_rational_new_no_reduce2(CLASS_OF(self),
bdat->den, bdat->num);
return f_muldiv(self,
adat->num, adat->den,
bdat->num, bdat->den, '/');
}
default:
return rb_num_coerce_bin(self, other, '/');
}
}
/*
* call-seq:
* rat.fdiv(numeric) -> float
*
* Performs division and returns the value as a float.
*
* For example:
*
* Rational(2, 3).fdiv(1) #=> 0.6666666666666666
* Rational(2, 3).fdiv(0.5) #=> 1.3333333333333333
* Rational(2).fdiv(3) #=> 0.6666666666666666
*/
static VALUE
nurat_fdiv(VALUE self, VALUE other)
{
if (f_zero_p(other))
return f_div(self, f_to_f(other));
return f_to_f(f_div(self, other));
}
extern VALUE rb_fexpt(VALUE x, VALUE y);
/*
* call-seq:
* rat ** numeric -> numeric_result
*
* Performs exponentiation.
*
* For example:
*
* Rational(2) ** Rational(3) #=> (8/1)
* Rational(10) ** -2 #=> (1/100)
* Rational(10) ** -2.0 #=> 0.01
* Rational(-4) ** Rational(1,2) #=> (1.2246063538223773e-16+2.0i)
* Rational(1, 2) ** 0 #=> (1/1)
* Rational(1, 2) ** 0.0 #=> 1.0
*/
static VALUE
nurat_expt(VALUE self, VALUE other)
{
if (k_exact_zero_p(other))
return f_rational_new_bang1(CLASS_OF(self), ONE);
if (k_rational_p(other)) {
get_dat1(other);
if (f_one_p(dat->den))
other = dat->num; /* c14n */
}
switch (TYPE(other)) {
case T_FIXNUM:
{
VALUE num, den;
get_dat1(self);
switch (FIX2INT(f_cmp(other, ZERO))) {
case 1:
num = f_expt(dat->num, other);
den = f_expt(dat->den, other);
break;
case -1:
num = f_expt(dat->den, f_negate(other));
den = f_expt(dat->num, f_negate(other));
break;
default:
num = ONE;
den = ONE;
break;
}
return f_rational_new2(CLASS_OF(self), num, den);
}
case T_BIGNUM:
rb_warn("in a**b, b may be too big");
/* fall through */
case T_FLOAT:
case T_RATIONAL:
return rb_fexpt(f_to_f(self), other);
default:
return rb_num_coerce_bin(self, other, id_expt);
}
}
/*
* call-seq:
* rat <=> numeric -> -1, 0, +1 or nil
*
* Performs comparison and returns -1, 0, or +1.
*
* For example:
*
* Rational(2, 3) <=> Rational(2, 3) #=> 0
* Rational(5) <=> 5 #=> 0
* Rational(2,3) <=> Rational(1,3) #=> 1
* Rational(1,3) <=> 1 #=> -1
* Rational(1,3) <=> 0.3 #=> 1
*/
static VALUE
nurat_cmp(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
{
get_dat1(self);
if (FIXNUM_P(dat->den) && FIX2LONG(dat->den) == 1)
return f_cmp(dat->num, other); /* c14n */
return f_cmp(self, f_rational_new_bang1(CLASS_OF(self), other));
}
case T_FLOAT:
return f_cmp(f_to_f(self), other);
case T_RATIONAL:
{
VALUE num1, num2;
get_dat2(self, other);
if (FIXNUM_P(adat->num) && FIXNUM_P(adat->den) &&
FIXNUM_P(bdat->num) && FIXNUM_P(bdat->den)) {
num1 = f_imul(FIX2LONG(adat->num), FIX2LONG(bdat->den));
num2 = f_imul(FIX2LONG(bdat->num), FIX2LONG(adat->den));
}
else {
num1 = f_mul(adat->num, bdat->den);
num2 = f_mul(bdat->num, adat->den);
}
return f_cmp(f_sub(num1, num2), ZERO);
}
default:
return rb_num_coerce_cmp(self, other, id_cmp);
}
}
/*
* call-seq:
* rat == object -> true or false
*
* Returns true if rat equals object numerically.
*
* For example:
*
* Rational(2, 3) == Rational(2, 3) #=> true
* Rational(5) == 5 #=> true
* Rational(0) == 0.0 #=> true
* Rational('1/3') == 0.33 #=> false
* Rational('1/2') == '1/2' #=> false
*/
static VALUE
nurat_eqeq_p(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
{
get_dat1(self);
if (f_zero_p(dat->num) && f_zero_p(other))
return Qtrue;
if (!FIXNUM_P(dat->den))
return Qfalse;
if (FIX2LONG(dat->den) != 1)
return Qfalse;
if (f_eqeq_p(dat->num, other))
return Qtrue;
return Qfalse;
}
case T_FLOAT:
return f_eqeq_p(f_to_f(self), other);
case T_RATIONAL:
{
get_dat2(self, other);
if (f_zero_p(adat->num) && f_zero_p(bdat->num))
return Qtrue;
return f_boolcast(f_eqeq_p(adat->num, bdat->num) &&
f_eqeq_p(adat->den, bdat->den));
}
default:
return f_eqeq_p(other, self);
}
}
/* :nodoc: */
static VALUE
nurat_coerce(VALUE self, VALUE other)
{
switch (TYPE(other)) {
case T_FIXNUM:
case T_BIGNUM:
return rb_assoc_new(f_rational_new_bang1(CLASS_OF(self), other), self);
case T_FLOAT:
return rb_assoc_new(other, f_to_f(self));
case T_RATIONAL:
return rb_assoc_new(other, self);
case T_COMPLEX:
if (k_exact_zero_p(RCOMPLEX(other)->imag))
return rb_assoc_new(f_rational_new_bang1
(CLASS_OF(self), RCOMPLEX(other)->real), self);
}
rb_raise(rb_eTypeError, "%s can't be coerced into %s",
rb_obj_classname(other), rb_obj_classname(self));
return Qnil;
}
#if 0
/* :nodoc: */
static VALUE
nurat_idiv(VALUE self, VALUE other)
{
return f_idiv(self, other);
}
/* :nodoc: */
static VALUE
nurat_quot(VALUE self, VALUE other)
{
return f_truncate(f_div(self, other));
}
/* :nodoc: */
static VALUE
nurat_quotrem(VALUE self, VALUE other)
{
VALUE val = f_truncate(f_div(self, other));
return rb_assoc_new(val, f_sub(self, f_mul(other, val)));
}
#endif
#if 0
/* :nodoc: */
static VALUE
nurat_true(VALUE self)
{
return Qtrue;
}
#endif
static VALUE
nurat_floor(VALUE self)
{
get_dat1(self);
return f_idiv(dat->num, dat->den);
}
static VALUE
nurat_ceil(VALUE self)
{
get_dat1(self);
return f_negate(f_idiv(f_negate(dat->num), dat->den));
}
/*
* call-seq:
* rat.to_i -> integer
*
* Returns the truncated value as an integer.
*
* Equivalent to
* rat.truncate.
*
* For example:
*
* Rational(2, 3).to_i #=> 0
* Rational(3).to_i #=> 3
* Rational(300.6).to_i #=> 300
* Rational(98,71).to_i #=> 1
* Rational(-30,2).to_i #=> -15
*/
static VALUE
nurat_truncate(VALUE self)
{
get_dat1(self);
if (f_negative_p(dat->num))
return f_negate(f_idiv(f_negate(dat->num), dat->den));
return f_idiv(dat->num, dat->den);
}
static VALUE
nurat_round(VALUE self)
{
VALUE num, den, neg;
get_dat1(self);
num = dat->num;
den = dat->den;
neg = f_negative_p(num);
if (neg)
num = f_negate(num);
num = f_add(f_mul(num, TWO), den);
den = f_mul(den, TWO);
num = f_idiv(num, den);
if (neg)
num = f_negate(num);
return num;
}
static VALUE
f_round_common(int argc, VALUE *argv, VALUE self, VALUE (*func)(VALUE))
{
VALUE n, b, s;
if (argc == 0)
return (*func)(self);
rb_scan_args(argc, argv, "01", &n);
if (!k_integer_p(n))
rb_raise(rb_eTypeError, "not an integer");
b = f_expt(INT2FIX(10), n);
s = f_mul(self, b);
s = (*func)(s);
s = f_div(f_rational_new_bang1(CLASS_OF(self), s), b);
if (f_lt_p(n, ONE))
s = f_to_i(s);
return s;
}
/*
* call-seq:
* rat.floor -> integer
* rat.floor(precision=0) -> rational
*
* Returns the truncated value (toward negative infinity).
*
* For example:
*
* Rational(3).floor #=> 3
* Rational(2, 3).floor #=> 0
* Rational(-3, 2).floor #=> -1
*
* decimal - 1 2 3 . 4 5 6
* ^ ^ ^ ^ ^ ^
* precision -3 -2 -1 0 +1 +2
*
* '%f' % Rational('-123.456').floor(+1) #=> "-123.500000"
* '%f' % Rational('-123.456').floor(-1) #=> "-130.000000"
*/
static VALUE
nurat_floor_n(int argc, VALUE *argv, VALUE self)
{
return f_round_common(argc, argv, self, nurat_floor);
}
/*
* call-seq:
* rat.ceil -> integer
* rat.ceil(precision=0) -> rational
*
* Returns the truncated value (toward positive infinity).
*
* For example:
*
* Rational(3).ceil #=> 3
* Rational(2, 3).ceil #=> 1
* Rational(-3, 2).ceil #=> -1
*
* decimal - 1 2 3 . 4 5 6
* ^ ^ ^ ^ ^ ^
* precision -3 -2 -1 0 +1 +2
*
* '%f' % Rational('-123.456').ceil(+1) #=> "-123.400000"
* '%f' % Rational('-123.456').ceil(-1) #=> "-120.000000"
*/
static VALUE
nurat_ceil_n(int argc, VALUE *argv, VALUE self)
{
return f_round_common(argc, argv, self, nurat_ceil);
}
/*
* call-seq:
* rat.truncate -> integer
* rat.truncate(precision=0) -> rational
*
* Returns the truncated value (toward zero).
*
* For example:
*
* Rational(3).truncate #=> 3
* Rational(2, 3).truncate #=> 0
* Rational(-3, 2).truncate #=> -1
*
* decimal - 1 2 3 . 4 5 6
* ^ ^ ^ ^ ^ ^
* precision -3 -2 -1 0 +1 +2
*
* '%f' % Rational('-123.456').truncate(+1) #=> "-123.400000"
* '%f' % Rational('-123.456').truncate(-1) #=> "-120.000000"
*/
static VALUE
nurat_truncate_n(int argc, VALUE *argv, VALUE self)
{
return f_round_common(argc, argv, self, nurat_truncate);
}
/*
* call-seq:
* rat.round -> integer
* rat.round(precision=0) -> rational
*
* Returns the truncated value (toward the nearest integer;
* 0.5 => 1; -0.5 => -1).
*
* For example:
*
* Rational(3).round #=> 3
* Rational(2, 3).round #=> 1
* Rational(-3, 2).round #=> -2
*
* decimal - 1 2 3 . 4 5 6
* ^ ^ ^ ^ ^ ^
* precision -3 -2 -1 0 +1 +2
*
* '%f' % Rational('-123.456').round(+1) #=> "-123.500000"
* '%f' % Rational('-123.456').round(-1) #=> "-120.000000"
*/
static VALUE
nurat_round_n(int argc, VALUE *argv, VALUE self)
{
return f_round_common(argc, argv, self, nurat_round);
}
/*
* call-seq:
* rat.to_f -> float
*
* Return the value as a float.
*
* For example:
*
* Rational(2).to_f #=> 2.0
* Rational(9, 4).to_f #=> 2.25
* Rational(-3, 4).to_f #=> -0.75
* Rational(20, 3).to_f #=> 6.666666666666667
*/
static VALUE
nurat_to_f(VALUE self)
{
get_dat1(self);
return f_fdiv(dat->num, dat->den);
}
/*
* call-seq:
* rat.to_r -> self
*
* Returns self.
*
* For example:
*
* Rational(2).to_r #=> (2/1)
* Rational(-8, 6).to_r #=> (-4/3)
*/
static VALUE
nurat_to_r(VALUE self)
{
return self;
}
/* :nodoc: */
static VALUE
nurat_hash(VALUE self)
{
long v, h[2];
VALUE n;
get_dat1(self);
n = rb_hash(dat->num);
h[0] = NUM2LONG(n);
n = rb_hash(dat->den);
h[1] = NUM2LONG(n);
v = rb_memhash(h, sizeof(h));
return LONG2FIX(v);
}
static VALUE
f_format(VALUE self, VALUE (*func)(VALUE))
{
VALUE s;
get_dat1(self);
s = (*func)(dat->num);
rb_str_cat2(s, "/");
rb_str_concat(s, (*func)(dat->den));
return s;
}
/*
* call-seq:
* rat.to_s -> string
*
* Returns the value as a string.
*
* For example:
*
* Rational(2).to_s #=> "2/1"
* Rational(-8, 6).to_s #=> "-4/3"
* Rational('0.5').to_s #=> "1/2"
*/
static VALUE
nurat_to_s(VALUE self)
{
return f_format(self, f_to_s);
}
/*
* call-seq:
* rat.inspect -> string
*
* Returns the value as a string for inspection.
*
* For example:
*
* Rational(2).inspect #=> "(2/1)"
* Rational(-8, 6).inspect #=> "(-4/3)"
* Rational('0.5').inspect #=> "(1/2)"
*/
static VALUE
nurat_inspect(VALUE self)
{
VALUE s;
s = rb_usascii_str_new2("(");
rb_str_concat(s, f_format(self, f_inspect));
rb_str_cat2(s, ")");
return s;
}
/* :nodoc: */
static VALUE
nurat_marshal_dump(VALUE self)
{
VALUE a;
get_dat1(self);
a = rb_assoc_new(dat->num, dat->den);
rb_copy_generic_ivar(a, self);
return a;
}
/* :nodoc: */
static VALUE
nurat_marshal_load(VALUE self, VALUE a)
{
get_dat1(self);
dat->num = RARRAY_PTR(a)[0];
dat->den = RARRAY_PTR(a)[1];
rb_copy_generic_ivar(self, a);
if (f_zero_p(dat->den))
rb_raise_zerodiv();
return self;
}
/* --- */
VALUE
rb_rational_reciprocal(VALUE x)
{
get_dat1(x);
return f_rational_new_no_reduce2(CLASS_OF(x), dat->den, dat->num);
}
/*
* call-seq:
* int.gcd(int2) -> integer
*
* Returns the greatest common divisor (always positive). 0.gcd(x)
* and x.gcd(0) return abs(x).
*
* For example:
*
* 2.gcd(2) #=> 2
* 3.gcd(-7) #=> 1
* ((1<<31)-1).gcd((1<<61)-1) #=> 1
*/
VALUE
rb_gcd(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return f_gcd(self, other);
}
/*
* call-seq:
* int.lcm(int2) -> integer
*
* Returns the least common multiple (always positive). 0.lcm(x) and
* x.lcm(0) return zero.
*
* For example:
*
* 2.lcm(2) #=> 2
* 3.lcm(-7) #=> 21
* ((1<<31)-1).lcm((1<<61)-1) #=> 4951760154835678088235319297
*/
VALUE
rb_lcm(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return f_lcm(self, other);
}
/*
* call-seq:
* int.gcdlcm(int2) -> array
*
* Returns an array; [int.gcd(int2), int.lcm(int2)].
*
* For example:
*
* 2.gcdlcm(2) #=> [2, 2]
* 3.gcdlcm(-7) #=> [1, 21]
* ((1<<31)-1).gcdlcm((1<<61)-1) #=> [1, 4951760154835678088235319297]
*/
VALUE
rb_gcdlcm(VALUE self, VALUE other)
{
other = nurat_int_value(other);
return rb_assoc_new(f_gcd(self, other), f_lcm(self, other));
}
VALUE
rb_rational_raw(VALUE x, VALUE y)
{
return nurat_s_new_internal(rb_cRational, x, y);
}
VALUE
rb_rational_new(VALUE x, VALUE y)
{
return nurat_s_canonicalize_internal(rb_cRational, x, y);
}
static VALUE nurat_s_convert(int argc, VALUE *argv, VALUE klass);
VALUE
rb_Rational(VALUE x, VALUE y)
{
VALUE a[2];
a[0] = x;
a[1] = y;
return nurat_s_convert(2, a, rb_cRational);
}
#define id_numerator rb_intern("numerator")
#define f_numerator(x) rb_funcall(x, id_numerator, 0)
#define id_denominator rb_intern("denominator")
#define f_denominator(x) rb_funcall(x, id_denominator, 0)
#define id_to_r rb_intern("to_r")
#define f_to_r(x) rb_funcall(x, id_to_r, 0)
/*
* call-seq:
* num.numerator -> integer
*
* Returns the numerator.
*/
static VALUE
numeric_numerator(VALUE self)
{
return f_numerator(f_to_r(self));
}
/*
* call-seq:
* num.denominator -> integer
*
* Returns the denominator (always positive).
*/
static VALUE
numeric_denominator(VALUE self)
{
return f_denominator(f_to_r(self));
}
/*
* call-seq:
* int.numerator -> self
*
* Returns self.
*/
static VALUE
integer_numerator(VALUE self)
{
return self;
}
/*
* call-seq:
* int.denominator -> 1
*
* Returns 1.
*/
static VALUE
integer_denominator(VALUE self)
{
return INT2FIX(1);
}
/*
* call-seq:
* flo.numerator -> integer
*
* Returns the numerator. The result is machine dependent.
*
* For example:
*
* n = 0.3.numerator #=> 5404319552844595
* d = 0.3.denominator #=> 18014398509481984
* n.fdiv(d) #=> 0.3
*/
static VALUE
float_numerator(VALUE self)
{
double d = RFLOAT_VALUE(self);
if (isinf(d) || isnan(d))
return self;
return rb_call_super(0, 0);
}
/*
* call-seq:
* flo.denominator -> integer
*
* Returns the denominator (always positive). The result is machine
* dependent.
*
* See numerator.
*/
static VALUE
float_denominator(VALUE self)
{
double d = RFLOAT_VALUE(self);
if (isinf(d) || isnan(d))
return INT2FIX(1);
return rb_call_super(0, 0);
}
/*
* call-seq:
* nil.to_r -> (0/1)
*
* Returns zero as a rational.
*/
static VALUE
nilclass_to_r(VALUE self)
{
return rb_rational_new1(INT2FIX(0));
}
/*
* call-seq:
* int.to_r -> rational
*
* Returns the value as a rational.
*
* For example:
*
* 1.to_r #=> (1/1)
* (1<<64).to_r #=> (18446744073709551616/1)
*/
static VALUE
integer_to_r(VALUE self)
{
return rb_rational_new1(self);
}
static void
float_decode_internal(VALUE self, VALUE *rf, VALUE *rn)
{
double f;
int n;
f = frexp(RFLOAT_VALUE(self), &n);
f = ldexp(f, DBL_MANT_DIG);
n -= DBL_MANT_DIG;
*rf = rb_dbl2big(f);
*rn = INT2FIX(n);
}
#if 0
static VALUE
float_decode(VALUE self)
{
VALUE f, n;
float_decode_internal(self, &f, &n);
return rb_assoc_new(f, n);
}
#endif
#define id_lshift rb_intern("<<")
#define f_lshift(x,n) rb_funcall(x, id_lshift, 1, n)
/*
* call-seq:
* flt.to_r -> rational
*
* Returns the value as a rational.
*
* NOTE: 0.3.to_r isn't the same as '0.3'.to_r. The latter is
* equivalent to '3/10'.to_r, but the former isn't so.
*
* For example:
*
* 2.0.to_r #=> (2/1)
* 2.5.to_r #=> (5/2)
* -0.75.to_r #=> (-3/4)
* 0.0.to_r #=> (0/1)
*/
static VALUE
float_to_r(VALUE self)
{
VALUE f, n;
float_decode_internal(self, &f, &n);
#if FLT_RADIX == 2
{
long ln = FIX2LONG(n);
if (ln == 0)
return f_to_r(f);
if (ln > 0)
return f_to_r(f_lshift(f, n));
ln = -ln;
return rb_rational_new2(f, f_lshift(ONE, INT2FIX(ln)));
}
#else
return f_to_r(f_mul(f, f_expt(INT2FIX(FLT_RADIX), n)));
#endif
}
static VALUE rat_pat, an_e_pat, a_dot_pat, underscores_pat, an_underscore;
#define WS "\\s*"
#define DIGITS "(?:[0-9](?:_[0-9]|[0-9])*)"
#define NUMERATOR "(?:" DIGITS "?\\.)?" DIGITS "(?:[eE][-+]?" DIGITS ")?"
#define DENOMINATOR DIGITS
#define PATTERN "\\A" WS "([-+])?(" NUMERATOR ")(?:\\/(" DENOMINATOR "))?" WS
static void
make_patterns(void)
{
static const char rat_pat_source[] = PATTERN;
static const char an_e_pat_source[] = "[eE]";
static const char a_dot_pat_source[] = "\\.";
static const char underscores_pat_source[] = "_+";
if (rat_pat) return;
rat_pat = rb_reg_new(rat_pat_source, sizeof rat_pat_source - 1, 0);
rb_gc_register_mark_object(rat_pat);
an_e_pat = rb_reg_new(an_e_pat_source, sizeof an_e_pat_source - 1, 0);
rb_gc_register_mark_object(an_e_pat);
a_dot_pat = rb_reg_new(a_dot_pat_source, sizeof a_dot_pat_source - 1, 0);
rb_gc_register_mark_object(a_dot_pat);
underscores_pat = rb_reg_new(underscores_pat_source,
sizeof underscores_pat_source - 1, 0);
rb_gc_register_mark_object(underscores_pat);
an_underscore = rb_usascii_str_new2("_");
rb_gc_register_mark_object(an_underscore);
}
#define id_match rb_intern("match")
#define f_match(x,y) rb_funcall(x, id_match, 1, y)
#define id_aref rb_intern("[]")
#define f_aref(x,y) rb_funcall(x, id_aref, 1, y)
#define id_post_match rb_intern("post_match")
#define f_post_match(x) rb_funcall(x, id_post_match, 0)
#define id_split rb_intern("split")
#define f_split(x,y) rb_funcall(x, id_split, 1, y)
#include <ctype.h>
static VALUE
string_to_r_internal(VALUE self)
{
VALUE s, m;
s = self;
if (RSTRING_LEN(s) == 0)
return rb_assoc_new(Qnil, self);
m = f_match(rat_pat, s);
if (!NIL_P(m)) {
VALUE v, ifp, exp, ip, fp;
VALUE si = f_aref(m, INT2FIX(1));
VALUE nu = f_aref(m, INT2FIX(2));
VALUE de = f_aref(m, INT2FIX(3));
VALUE re = f_post_match(m);
{
VALUE a;
a = f_split(nu, an_e_pat);
ifp = RARRAY_PTR(a)[0];
if (RARRAY_LEN(a) != 2)
exp = Qnil;
else
exp = RARRAY_PTR(a)[1];
a = f_split(ifp, a_dot_pat);
ip = RARRAY_PTR(a)[0];
if (RARRAY_LEN(a) != 2)
fp = Qnil;
else
fp = RARRAY_PTR(a)[1];
}
v = rb_rational_new1(f_to_i(ip));
if (!NIL_P(fp)) {
char *p = StringValuePtr(fp);
long count = 0;
VALUE l;
while (*p) {
if (rb_isdigit(*p))
count++;
p++;
}
l = f_expt(INT2FIX(10), LONG2NUM(count));
v = f_mul(v, l);
v = f_add(v, f_to_i(fp));
v = f_div(v, l);
}
if (!NIL_P(si) && *StringValuePtr(si) == '-')
v = f_negate(v);
if (!NIL_P(exp))
v = f_mul(v, f_expt(INT2FIX(10), f_to_i(exp)));
#if 0
if (!NIL_P(de) && (!NIL_P(fp) || !NIL_P(exp)))
return rb_assoc_new(v, rb_usascii_str_new2("dummy"));
#endif
if (!NIL_P(de))
v = f_div(v, f_to_i(de));
return rb_assoc_new(v, re);
}
return rb_assoc_new(Qnil, self);
}
static VALUE
string_to_r_strict(VALUE self)
{
VALUE a = string_to_r_internal(self);
if (NIL_P(RARRAY_PTR(a)[0]) || RSTRING_LEN(RARRAY_PTR(a)[1]) > 0) {
VALUE s = f_inspect(self);
rb_raise(rb_eArgError, "invalid value for convert(): %s",
StringValuePtr(s));
}
return RARRAY_PTR(a)[0];
}
#define id_gsub rb_intern("gsub")
#define f_gsub(x,y,z) rb_funcall(x, id_gsub, 2, y, z)
/*
* call-seq:
* str.to_r -> rational
*
* Returns a rational which denotes the string form. The parser
* ignores leading whitespaces and trailing garbage. Any digit
* sequences can be separeted by an underscore. Returns zero for null
* or garbage string.
*
* NOTE: '0.3'.to_r isn't the same as 0.3.to_r. The former is
* equivalent to '3/10'.to_r, but the latter isn't so.
*
* For example:
*
* ' 2 '.to_r #=> (2/1)
* '300/2'.to_r #=> (150/1)
* '-9.2'.to_r #=> (-46/5)
* '-9.2e2'.to_r #=> (-920/1)
* '1_234_567'.to_r #=> (1234567/1)
* '21 june 09'.to_r #=> (21/1)
* '21/06/09'.to_r #=> (7/2)
* 'bwv 1079'.to_r #=> (0/1)
*/
static VALUE
string_to_r(VALUE self)
{
VALUE s, a, backref;
backref = rb_backref_get();
rb_match_busy(backref);
s = f_gsub(self, underscores_pat, an_underscore);
a = string_to_r_internal(s);
rb_backref_set(backref);
if (!NIL_P(RARRAY_PTR(a)[0]))
return RARRAY_PTR(a)[0];
return rb_rational_new1(INT2FIX(0));
}
#define id_to_r rb_intern("to_r")
#define f_to_r(x) rb_funcall(x, id_to_r, 0)
static VALUE
nurat_s_convert(int argc, VALUE *argv, VALUE klass)
{
VALUE a1, a2, backref;
rb_scan_args(argc, argv, "11", &a1, &a2);
if (NIL_P(a1) || (argc == 2 && NIL_P(a2)))
rb_raise(rb_eTypeError, "can't convert nil into Rational");
switch (TYPE(a1)) {
case T_COMPLEX:
if (k_exact_zero_p(RCOMPLEX(a1)->imag))
a1 = RCOMPLEX(a1)->real;
}
switch (TYPE(a2)) {
case T_COMPLEX:
if (k_exact_zero_p(RCOMPLEX(a2)->imag))
a2 = RCOMPLEX(a2)->real;
}
backref = rb_backref_get();
rb_match_busy(backref);
switch (TYPE(a1)) {
case T_FIXNUM:
case T_BIGNUM:
break;
case T_FLOAT:
a1 = f_to_r(a1);
break;
case T_STRING:
a1 = string_to_r_strict(a1);
break;
}
switch (TYPE(a2)) {
case T_FIXNUM:
case T_BIGNUM:
break;
case T_FLOAT:
a2 = f_to_r(a2);
break;
case T_STRING:
a2 = string_to_r_strict(a2);
break;
}
rb_backref_set(backref);
switch (TYPE(a1)) {
case T_RATIONAL:
if (argc == 1 || (k_exact_one_p(a2)))
return a1;
}
if (argc == 1) {
if (!(k_numeric_p(a1) && k_integer_p(a1)))
return rb_convert_type(a1, T_RATIONAL, "Rational", "to_r");
}
else {
if ((k_numeric_p(a1) && k_numeric_p(a2)) &&
(!f_integer_p(a1) || !f_integer_p(a2)))
return f_div(a1, a2);
}
{
VALUE argv2[2];
argv2[0] = a1;
argv2[1] = a2;
return nurat_s_new(argc, argv2, klass);
}
}
/*
* A rational number can be represented as a paired integer number;
* a/b (b>0). Where a is numerator and b is denominator. Integer a
* equals rational a/1 mathematically.
*
* In ruby, you can create rational object with Rational or to_r
* method. The return values will be irreducible.
*
* Rational(1) #=> (1/1)
* Rational(2, 3) #=> (2/3)
* Rational(4, -6) #=> (-2/3)
* 3.to_r #=> (3/1)
*
* You can also create ratioanl object from floating-point numbers or
* strings.
*
* Rational(0.3) #=> (5404319552844595/18014398509481984)
* Rational('0.3') #=> (3/10)
* Rational('2/3') #=> (2/3)
*
* 0.3.to_r #=> (5404319552844595/18014398509481984)
* '0.3'.to_r #=> (3/10)
* '2/3'.to_r #=> (2/3)
*
* A rational object is an exact number, which helps you to write
* program without any rounding errors.
*
* 10.times.inject(0){|t,| t + 0.1} #=> 0.9999999999999999
* 10.times.inject(0){|t,| t + Rational('0.1')} #=> (1/1)
*
* However, when an expression has inexact factor (numerical value or
* operation), will produce an inexact result.
*
* Rational(10) / 3 #=> (10/3)
* Rational(10) / 3.0 #=> 3.3333333333333335
*
* Rational(-8) ** Rational(1, 3)
* #=> (1.0000000000000002+1.7320508075688772i)
*/
void
Init_Rational(void)
{
#undef rb_intern
#define rb_intern(str) rb_intern_const(str)
assert(fprintf(stderr, "assert() is now active\n"));
id_abs = rb_intern("abs");
id_cmp = rb_intern("<=>");
id_convert = rb_intern("convert");
id_eqeq_p = rb_intern("==");
id_expt = rb_intern("**");
id_fdiv = rb_intern("fdiv");
id_floor = rb_intern("floor");
id_idiv = rb_intern("div");
id_inspect = rb_intern("inspect");
id_integer_p = rb_intern("integer?");
id_negate = rb_intern("-@");
id_to_f = rb_intern("to_f");
id_to_i = rb_intern("to_i");
id_to_s = rb_intern("to_s");
id_truncate = rb_intern("truncate");
rb_cRational = rb_define_class("Rational", rb_cNumeric);
rb_define_alloc_func(rb_cRational, nurat_s_alloc);
rb_undef_method(CLASS_OF(rb_cRational), "allocate");
#if 0
rb_define_private_method(CLASS_OF(rb_cRational), "new!", nurat_s_new_bang, -1);
rb_define_private_method(CLASS_OF(rb_cRational), "new", nurat_s_new, -1);
#else
rb_undef_method(CLASS_OF(rb_cRational), "new");
#endif
rb_define_global_function("Rational", nurat_f_rational, -1);
rb_define_method(rb_cRational, "numerator", nurat_numerator, 0);
rb_define_method(rb_cRational, "denominator", nurat_denominator, 0);
rb_define_method(rb_cRational, "+", nurat_add, 1);
rb_define_method(rb_cRational, "-", nurat_sub, 1);
rb_define_method(rb_cRational, "*", nurat_mul, 1);
rb_define_method(rb_cRational, "/", nurat_div, 1);
rb_define_method(rb_cRational, "quo", nurat_div, 1);
rb_define_method(rb_cRational, "fdiv", nurat_fdiv, 1);
rb_define_method(rb_cRational, "**", nurat_expt, 1);
rb_define_method(rb_cRational, "<=>", nurat_cmp, 1);
rb_define_method(rb_cRational, "==", nurat_eqeq_p, 1);
rb_define_method(rb_cRational, "coerce", nurat_coerce, 1);
#if 0 /* NUBY */
rb_define_method(rb_cRational, "//", nurat_idiv, 1);
#endif
#if 0
rb_define_method(rb_cRational, "quot", nurat_quot, 1);
rb_define_method(rb_cRational, "quotrem", nurat_quotrem, 1);
#endif
#if 0
rb_define_method(rb_cRational, "rational?", nurat_true, 0);
rb_define_method(rb_cRational, "exact?", nurat_true, 0);
#endif
rb_define_method(rb_cRational, "floor", nurat_floor_n, -1);
rb_define_method(rb_cRational, "ceil", nurat_ceil_n, -1);
rb_define_method(rb_cRational, "truncate", nurat_truncate_n, -1);
rb_define_method(rb_cRational, "round", nurat_round_n, -1);
rb_define_method(rb_cRational, "to_i", nurat_truncate, 0);
rb_define_method(rb_cRational, "to_f", nurat_to_f, 0);
rb_define_method(rb_cRational, "to_r", nurat_to_r, 0);
rb_define_method(rb_cRational, "hash", nurat_hash, 0);
rb_define_method(rb_cRational, "to_s", nurat_to_s, 0);
rb_define_method(rb_cRational, "inspect", nurat_inspect, 0);
rb_define_method(rb_cRational, "marshal_dump", nurat_marshal_dump, 0);
rb_define_method(rb_cRational, "marshal_load", nurat_marshal_load, 1);
/* --- */
rb_define_method(rb_cInteger, "gcd", rb_gcd, 1);
rb_define_method(rb_cInteger, "lcm", rb_lcm, 1);
rb_define_method(rb_cInteger, "gcdlcm", rb_gcdlcm, 1);
rb_define_method(rb_cNumeric, "numerator", numeric_numerator, 0);
rb_define_method(rb_cNumeric, "denominator", numeric_denominator, 0);
rb_define_method(rb_cInteger, "numerator", integer_numerator, 0);
rb_define_method(rb_cInteger, "denominator", integer_denominator, 0);
rb_define_method(rb_cFloat, "numerator", float_numerator, 0);
rb_define_method(rb_cFloat, "denominator", float_denominator, 0);
rb_define_method(rb_cNilClass, "to_r", nilclass_to_r, 0);
rb_define_method(rb_cInteger, "to_r", integer_to_r, 0);
rb_define_method(rb_cFloat, "to_r", float_to_r, 0);
make_patterns();
rb_define_method(rb_cString, "to_r", string_to_r, 0);
rb_define_private_method(CLASS_OF(rb_cRational), "convert", nurat_s_convert, -1);
}
/*
Local variables:
c-file-style: "ruby"
End:
*/