Class: GMP::Q

Inherits:
Numeric
  • Object
show all
Defined in:
ext/gmpq.c,
ext/gmp.c,
ext/gmpq.c

Overview

GMP Multiple Precision Rational Number.

Instances of this class can store variables of the type mpq_t. This class also contains many methods that act as the functions for mpq_t variables, as well as a few methods that attempt to make this library more Ruby-ish.

The following list is just a simple checklist for me, really. A better reference should be found in the rdocs.

Ruby method  C Extension function  GMP function
to_d         r_gmpq_to_d           mpq_get_d
to_s         r_gmpq_to_s           ?
add          r_gmpq_add            mpq_add
sub          r_gmpq_sub            mpq_sub
mul          r_gmpq_mul            mpq_mul
div          r_gmpq_div            mpq_div
-@           r_gmpq_neg            mpq_neg
neg          r_gmpq_neg            mpq_neg
neg!         r_gmpq_neg_self       mpq_neg
abs          r_gmpq_abs            mpq_abs
abs!         r_gmpq_abs_self       mpq_abs

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ Object 



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# File 'ext/gmp.c', line 39

static VALUE r_gmpq_initialize(int argc, VALUE *argv, VALUE self)
{
  MP_RAT *self_val, *arg_val;

  if (argc != 0) {
    mpq_get_struct(self, self_val);
    if (argc == 1 && GMPQ_P(argv[0])) {
      mpq_get_struct(argv[0], arg_val);
      mpq_set (self_val, arg_val);
    } else if (argc == 1 && STRING_P(argv[0])) {
      mpq_str_set (self_val, STR2CSTR(argv[0]));
    } else {
      mpz_set_value (mpq_numref(self_val), argv[0]);
      if (argc == 2) {
        mpz_set_value (mpq_denref(self_val), argv[1]);
        mpq_canonicalize(self_val);
      }
    }
  }
  return Qnil;
}

Class Method Details

.GMP::Q.new(arg) ⇒ Object

Creates a new GMP::Q rational, with arg as its value, converting where necessary.



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# File 'ext/gmpq.c', line 68

VALUE r_gmpqsg_new(int argc, VALUE *argv, VALUE klass)
{
  MP_RAT *res_val;
  VALUE res;

  (void)klass;

  if (argc > 2)
    rb_raise(rb_eArgError, "wrong # of arguments(%d for 0, 1 or 2)", argc);

  mpq_make_struct (res, res_val);
  mpq_init (res_val);
  rb_obj_call_init(res, argc, argv);
 
  return res;
}

Instance Method Details

#*(rat2) ⇒ Object

Multiplies rat1 with rat2. rat2 can be

  • GMP::Z

  • Fixnum

  • GMP::Q

  • GMP::F

  • Bignum



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# File 'ext/gmpq.c', line 307

VALUE r_gmpq_mul(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val_q, *res_val;
  MP_INT *arg_val_z, *tmp_z;
  VALUE res;
#if GMP >= 4
  unsigned long tmp_ui;
#endif

  mpq_get_struct(self, self_val);
  mpq_make_struct_init(res, res_val);

  if (GMPQ_P(arg)) {
    mpq_get_struct(arg,arg_val_q);
    mpq_mul(res_val, self_val, arg_val_q);
  } else if (GMPZ_P(arg)) {
    mpz_get_struct(arg,arg_val_z);
    mpz_temp_init(tmp_z);
    mpz_gcd(tmp_z, mpq_denref(self_val), arg_val_z);
    mpz_divexact(mpq_denref(res_val), mpq_denref(self_val), tmp_z);
    mpz_divexact(mpq_numref(res_val), arg_val_z, tmp_z);
    mpz_mul(mpq_numref(res_val), mpq_numref(res_val), mpq_numref(self_val));
    mpz_temp_free(tmp_z);
  } else if (FIXNUM_P(arg)) {
#if GMP >= 4
    if (FIX2INT(arg) > 0) {
      tmp_ui = mpz_gcd_ui(0, mpq_denref(self_val), FIX2INT(arg));
    } else if (FIX2INT(arg) < 0) {
      tmp_ui = mpz_gcd_ui(0, mpq_denref(self_val), -FIX2INT(arg));
    } else {
      mpz_set_ui(mpq_numref(res_val), 0);
      mpz_set_ui(mpq_denref(res_val), 1);
      return res;
    }
    mpz_divexact_ui(mpq_denref(res_val), mpq_denref(self_val), tmp_ui);
    mpz_mul_ui(mpq_numref(res_val), mpq_numref(self_val), FIX2INT(arg)/tmp_ui);
#else
    mpz_set(mpq_denref(res_val), mpq_denref(self_val));
    mpz_mul_si(mpq_numref(res_val), mpq_numref(self_val), FIX2INT(arg));
    mpq_canonicalize(res_val);
#endif
  } else if (GMPF_P(arg)) {
    return r_gmpf_mul(arg, self);
  } else if (BIGNUM_P(arg)) {
    mpz_temp_alloc(tmp_z);
    mpz_set_bignum(tmp_z, arg);
    mpz_gcd(mpq_denref(res_val), mpq_denref(self_val), tmp_z);
    mpz_divexact(mpq_numref(res_val), tmp_z, mpq_denref(res_val));
    mpz_divexact(mpq_denref(res_val), mpq_denref(self_val), mpq_denref(res_val));
    mpz_mul(mpq_numref(res_val), mpq_numref(res_val), mpq_numref(self_val));
    mpz_temp_free(tmp_z);
  } else {
    typeerror(ZQFXB);
  }
  return res;
}

#+(rat2) ⇒ Object

Adds rat1 to rat2. rat2 can be

  • GMP::Z

  • Fixnum

  • GMP::Q

  • GMP::F

  • Bignum



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# File 'ext/gmpq.c', line 204

VALUE r_gmpq_add(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val_q, *res_val;
  MP_INT *arg_val_z, *res_val_num;
  VALUE res;

  mpq_get_struct(self, self_val);
  mpq_make_struct_init(res, res_val);

  if (GMPQ_P(arg)) {
    mpq_get_struct(arg,arg_val_q);
    mpq_add(res_val, self_val, arg_val_q);
  } else if (GMPZ_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set(mpq_denref(res_val), mpq_denref(self_val));
    mpz_get_struct(arg, arg_val_z);
    mpz_mul(res_val_num, mpq_denref(self_val), arg_val_z);
    mpz_add(res_val_num, res_val_num, mpq_numref(self_val));
  } else if (FIXNUM_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set(mpq_denref(res_val), mpq_denref(self_val));
    mpz_mul_si(res_val_num, mpq_denref(self_val), FIX2INT(arg));
    mpz_add(res_val_num, res_val_num, mpq_numref(self_val));
  } else if (GMPF_P(arg)) {
    return r_gmpf_add(arg,self);
  } else if (BIGNUM_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set(mpq_denref(res_val), mpq_denref(self_val));
    mpz_set_bignum(res_val_num, arg);
    mpz_mul(res_val_num, res_val_num, mpq_denref(self_val));
    mpz_add(res_val_num, res_val_num, mpq_numref(self_val));
  } else {
    typeerror(ZQFXB);
  }
  return res;
}

#-(rat2) ⇒ Object

Subtracts rat2 from rat1. rat2 can be

  • GMP::Z

  • Fixnum

  • GMP::Q

  • GMP::F

  • Bignum



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# File 'ext/gmpq.c', line 252

VALUE r_gmpq_sub(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val_q, *res_val;
  MP_INT *arg_val_z, *res_val_num;
  MP_FLOAT *arg_val_f, *res_val_f;
  VALUE res;
  unsigned int prec;

  mpq_get_struct(self, self_val);
  mpq_make_struct_init(res, res_val);

  if (GMPQ_P(arg)) {
    mpq_get_struct(arg,arg_val_q);
    mpq_sub (res_val, self_val, arg_val_q);
  } else if (GMPZ_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set (mpq_denref(res_val), mpq_denref(self_val));
    mpz_get_struct(arg, arg_val_z);
    mpz_mul (res_val_num, mpq_denref(self_val), arg_val_z);
    mpz_neg (res_val_num, res_val_num);
    mpz_add (res_val_num, res_val_num, mpq_numref(self_val));
  } else if (FIXNUM_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set (mpq_denref(res_val), mpq_denref(self_val));
    mpz_mul_si (res_val_num, mpq_denref(self_val), -FIX2INT(arg));
    mpz_add (res_val_num, res_val_num, mpq_numref(self_val));
  } else if (GMPF_P(arg)) {
    mpf_get_struct_prec (arg, arg_val_f, prec);
    mpf_make_struct_init(res, res_val_f, prec);
    mpf_set_q (res_val_f, self_val);
    mpf_sub (res_val_f, res_val_f, arg_val_f);
  } else if (BIGNUM_P(arg)) {
    res_val_num = mpq_numref(res_val);
    mpz_set (mpq_denref(res_val), mpq_denref(self_val));
    mpz_set_bignum (res_val_num, arg);
    mpz_mul (res_val_num, res_val_num, mpq_denref(self_val));
    mpz_neg (res_val_num, res_val_num);
    mpz_add (res_val_num, res_val_num, mpq_numref(self_val));
  } else {
    typeerror (ZQFXB);
  }
  return res;
}

#-@ ⇒ Object

#/(rat2) ⇒ Object

Divides rat1 by rat2. rat2 can be

  • GMP::Z

  • Fixnum

  • GMP::Q

  • GMP::F

  • Bignum



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# File 'ext/gmpq.c', line 375

VALUE r_gmpq_div(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val_q, *res_val;
  MP_INT *arg_val_z, *tmp_z;
  MP_FLOAT *arg_val_f, *res_val_f;
  VALUE res;
  unsigned long tmp_ui, prec;

  mpq_get_struct(self, self_val);
  mpq_make_struct_init(res, res_val);

  if (GMPQ_P(arg)) {
    mpq_get_struct(arg,arg_val_q);
    if (mpz_sgn(mpq_numref(arg_val_q)) == 0)
      rb_raise(rb_eZeroDivError, "divided by 0");
    mpq_div(res_val, self_val, arg_val_q);
  } else if (GMPZ_P(arg)) {
    mpz_get_struct(arg,arg_val_z);
    mpz_temp_init(tmp_z);
    mpz_gcd(tmp_z, mpq_numref(self_val), arg_val_z);
    mpz_divexact(mpq_numref(res_val), mpq_numref(self_val), tmp_z);
    mpz_divexact(mpq_denref(res_val), arg_val_z, tmp_z);
    mpz_mul(mpq_denref(res_val), mpq_denref(res_val), mpq_denref(self_val));
    mpz_temp_free(tmp_z);
  } else if (FIXNUM_P(arg)) {
    if (FIX2INT(arg) == 0)
      rb_raise(rb_eZeroDivError, "divided by 0");
    if (FIX2INT(arg) > 0) {
      tmp_ui = mpz_gcd_ui(0, mpq_numref(self_val), FIX2INT(arg));
    } else {
      tmp_ui = mpz_gcd_ui(0, mpq_numref(self_val), -FIX2INT(arg));
    }
    mpz_divexact_ui(mpq_numref(res_val), mpq_numref(self_val), tmp_ui);
    mpz_mul_ui(mpq_denref(res_val), mpq_denref(self_val), FIX2INT(arg)/tmp_ui);
  } else if (GMPF_P(arg)) {
    mpf_get_struct_prec(arg, arg_val_f, prec);
    mpf_make_struct_init(res, res_val_f, prec);
    mpf_set_q(res_val_f, self_val);
    mpf_div(res_val_f, res_val_f, arg_val_f);
  } else if (BIGNUM_P(arg)) {
    mpz_temp_alloc(tmp_z);
    mpz_set_bignum(tmp_z, arg);
    mpz_gcd(mpq_numref(res_val), mpq_numref(self_val), tmp_z);
    mpz_divexact(mpq_denref(res_val), tmp_z, mpq_numref(res_val));
    mpz_divexact(mpq_numref(res_val), mpq_numref(self_val), mpq_numref(res_val));
    mpz_mul(mpq_denref(res_val), mpq_denref(res_val), mpq_denref(self_val));
    mpz_temp_free(tmp_z);
  } else {
    typeerror(ZQFXB);
  }
  return res;
}

#< ⇒ Object

#<= ⇒ Object

#<=>(arg) ⇒ Object

Comparing Rationals



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# File 'ext/gmpq.c', line 611

VALUE r_gmpq_cmp(VALUE self, VALUE arg)
{
  MP_RAT *self_val;
  int res;
  mpq_get_struct (self,self_val);
  res = mpq_cmp_value(self_val, arg);
  if (res > 0)
    return INT2FIX(1);
  else if (res == 0)
    return INT2FIX(0);
  else
    return INT2FIX(-1);
}

#==(arg) ⇒ Object 



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# File 'ext/gmpq.c', line 577

VALUE r_gmpq_eq(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val_q;
  MP_INT *arg_val_z;

  mpq_get_struct(self,self_val);
  if (GMPQ_P(arg)) {
    mpq_get_struct(arg,arg_val_q);
    return mpq_equal(self_val,arg_val_q)?Qtrue:Qfalse;
  } else if (GMPZ_P(arg)) {
    if (mpz_cmp_ui(mpq_denref(self_val), 1) != 0)
      return Qfalse;
    mpz_get_struct (arg, arg_val_z);
    return (mpz_cmp(mpq_numref(self_val),arg_val_z)==0)?Qtrue:Qfalse;
  } else if (FIXNUM_P(arg)) {
    if (mpz_cmp_ui(mpq_denref(self_val), 1) != 0)
      return Qfalse;
    return (mpz_cmp_ui(mpq_numref(self_val),FIX2INT(arg))==0)?Qtrue:Qfalse;
  } else if (BIGNUM_P(arg)) {
    if (mpz_cmp_ui(mpq_denref(self_val), 1) != 0)
      return Qfalse;
    mpz_temp_from_bignum(arg_val_z, arg);
    if (mpz_cmp (mpq_numref(self_val),arg_val_z) == 0) {
      mpz_temp_free (arg_val_z);
      return Qtrue;
    } else {
      mpz_temp_free (arg_val_z);
      return Qfalse;
    }
  } else {
    return Qfalse;
  }
}

#> ⇒ Object

#>= ⇒ Object

#abs ⇒ Object

call-seq:

rational.abs

From the GMP Manual:

Returns the absolute value of rational.



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# File 'ext/gmpq.c', line 481

VALUE r_gmpq_abs(VALUE self)
{
  MP_RAT *self_val, *res_val;
  VALUE res;
  mpq_get_struct(self, self_val);
  mpq_make_struct_init(res, res_val);
  mpz_abs (mpq_numref(res_val), mpq_numref(self_val));
  mpz_set (mpq_denref(res_val), mpq_denref(self_val));

  return res;
}

#abs! ⇒ Object

call-seq:

rational.abs!

From the GMP Manual:

Sets rational to its absolute value.



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# File 'ext/gmpq.c', line 503

VALUE r_gmpq_abs_self(VALUE self)
{
  MP_RAT *self_val;
  mpq_get_struct(self, self_val);
  mpz_abs (mpq_numref(self_val), mpq_numref(self_val));
  return Qnil;
}

#ceil ⇒ Object

#cmpabs ⇒ Object

#coerce(arg) ⇒ Object 



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# File 'ext/gmp.c', line 66

static VALUE r_gmpq_coerce(VALUE self, VALUE arg)
{
  return rb_assoc_new(r_gmpqsg_new(1, &arg, cGMP_Q), self);
}

#den ⇒ Object

#floor ⇒ Object

unsorted

#inv ⇒ Object 



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# File 'ext/gmpq.c', line 511

VALUE r_gmpq_inv(VALUE self)
{
  MP_RAT *self_val, *res_val;
  VALUE res;

  mpq_get_struct(self, self_val);
  if (mpq_sgn(self_val) == 0)
    rb_raise (rb_eZeroDivError, "divided by 0");
  mpq_make_struct_init(res, res_val);
  mpq_inv (res_val, self_val);

  return res;
}

#inv! ⇒ Object 



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# File 'ext/gmpq.c', line 525

VALUE r_gmpq_inv_self(VALUE self)
{
  MP_RAT *self_val;
  mpq_get_struct(self, self_val);
  if (mpq_sgn(self_val) == 0)
    rb_raise (rb_eZeroDivError, "divided by 0");
  mpq_inv (self_val, self_val);
  return Qnil;
}

#neg! ⇒ Object

call-seq:

rational.neg!

From the GMP Manual:

Sets rational to -rational.



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# File 'ext/gmpq.c', line 463

VALUE r_gmpq_neg_self(VALUE self)
{
  MP_RAT *self_val;
  mpq_get_struct(self, self_val);
  mpz_neg (mpq_numref(self_val), mpq_numref(self_val));
  return Qnil;
}

#num ⇒ Object

#sgn ⇒ Object

From the GMP Manual:

Returns +1 if rational > 0, 0 if rational == 0, and -1 if rational < 0.



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# File 'ext/gmpq.c', line 705

VALUE r_gmpq_sgn(VALUE self)
{
  MP_RAT *self_val;
  mpq_get_struct(self, self_val);
  return INT2FIX(mpq_sgn(self_val));
}

#rat2 ⇒ Object

Efficiently swaps the contents of rat1 with rat2.



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# File 'ext/gmpq.c', line 103

VALUE r_gmpq_swap(VALUE self, VALUE arg)
{
  MP_RAT *self_val, *arg_val;

  if (!GMPQ_P(arg)) {
    rb_raise(rb_eTypeError, "Can't swap GMP::Q with object of other class");
  }

  mpq_get_struct(self, self_val);
  mpq_get_struct(arg, arg_val);
  mpq_swap(self_val,arg_val);

  return Qnil;
}

#to_d ⇒ Object Also known as: to_f

Returns rational as an Float if rational fits in a Float.

Otherwise returns the least significant part of rational, with the same sign as rational.

If the exponent from the conversion is too big or too small to fit a double then the result is system dependent. For too big an infinity is returned when available. For too small 0.0 is normally returned. Hardware overflow, underflow and denorm traps may or may not occur.



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# File 'ext/gmpq.c', line 137

VALUE r_gmpq_to_d(VALUE self)
{
  MP_RAT *self_val;
  mpq_get_struct(self, self_val);

  return rb_float_new(mpq_get_d(self_val));
}

#to_s ⇒ Object

call-seq:

rational.to_s

Returns the decimal representation of rational, as a Ruby string.



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# File 'ext/gmpq.c', line 153

VALUE r_gmpq_to_s(VALUE self)
{
  MP_RAT *self_val;
  MP_INT *self_val_num, *self_val_den;
  char *str;
  VALUE res;
  int sizeinbase;
  int offset;

  //Data_Get_Struct (self, MP_RAT, self_val);
  mpq_get_struct(self, self_val)

  if (mpz_cmp_ui (mpq_denref (self_val), 1) == 0) {
    str = mpz_get_str (NULL, 10, mpq_numref (self_val));
    res = rb_str_new2 (str);
    free (str);
    return res;
  }

  self_val_num = mpq_numref (self_val);
  self_val_den = mpq_denref (self_val);

  sizeinbase = mpz_sizeinbase (self_val_num, 10) + mpz_sizeinbase (self_val_den, 10) + 3;
  str = malloc (sizeinbase);

  mpz_get_str (str, 10, self_val_num);
  offset = strlen (str);
  str[offset] = '/';
  mpz_get_str (str + offset + 1, 10, self_val_den);
  res = rb_str_new2(str);
  free (str);

  return res;
}

#trunc ⇒ Object