In Files

  • complex.c
  • numeric.c
  • rational.c

Numeric

Public Instance Methods

+num => num click to toggle source

Unary Plus—Returns the receiver’s value.

 
               static VALUE
num_uplus(VALUE num)
{
    return num;
}
            
-num => numeric click to toggle source

Unary Minus—Returns the receiver’s value, negated.

 
               static VALUE
num_uminus(VALUE num)
{
    VALUE zero;

    zero = INT2FIX(0);
    do_coerce(&zero, &num, Qtrue);

    return rb_funcall(zero, '-', 1, num);
}
            
num <=> other → 0 or nil click to toggle source

Returns zero if num equals other, nil otherwise.

 
               static VALUE
num_cmp(VALUE x, VALUE y)
{
    if (x == y) return INT2FIX(0);
    return Qnil;
}
            
abs => num or numeric click to toggle source

Returns the absolute value of num.

12.abs         #=> 12
(-34.56).abs   #=> 34.56
-34.56.abs     #=> 34.56
 
               static VALUE
num_abs(VALUE num)
{
    if (RTEST(rb_funcall(num, '<', 1, INT2FIX(0)))) {
        return rb_funcall(num, rb_intern("-@"), 0);
    }
    return num;
}
            
abs2() click to toggle source
 
               static VALUE
numeric_abs2(VALUE self)
{
    return f_mul(self, self);
}
            
angle → 0 or float click to toggle source

Returns 0 if the value is positive, pi otherwise.

 
               static VALUE
numeric_arg(VALUE self)
{
    if (f_positive_p(self))
        return INT2FIX(0);
    return rb_const_get(rb_mMath, id_PI);
}
            
arg → 0 or float click to toggle source

Returns 0 if the value is positive, pi otherwise.

 
               static VALUE
numeric_arg(VALUE self)
{
    if (f_positive_p(self))
        return INT2FIX(0);
    return rb_const_get(rb_mMath, id_PI);
}
            
ceil => integer click to toggle source

Returns the smallest Integer greater than or equal to num. Class Numeric achieves this by converting itself to a Float then invoking Float#ceil.

1.ceil        #=> 1
1.2.ceil      #=> 2
(-1.2).ceil   #=> -1
(-1.0).ceil   #=> -1
 
               static VALUE
num_ceil(VALUE num)
{
    return flo_ceil(rb_Float(num));
}
            
coerce(numeric) => array click to toggle source

If aNumeric is the same type as num, returns an array containing aNumeric and num. Otherwise, returns an array with both aNumeric and num represented as Float objects. This coercion mechanism is used by Ruby to handle mixed-type numeric operations: it is intended to find a compatible common type between the two operands of the operator.

1.coerce(2.5)   #=> [2.5, 1.0]
1.2.coerce(3)   #=> [3.0, 1.2]
1.coerce(2)     #=> [2, 1]
 
               static VALUE
num_coerce(VALUE x, VALUE y)
{
    if (CLASS_OF(x) == CLASS_OF(y))
        return rb_assoc_new(y, x);
    x = rb_Float(x);
    y = rb_Float(y);
    return rb_assoc_new(y, x);
}
            
conj() click to toggle source
 
               static VALUE
numeric_conj(VALUE self)
{
    return self;
}
            
conjugate() click to toggle source
 
               static VALUE
numeric_conj(VALUE self)
{
    return self;
}
            
denominator() click to toggle source
 
               static VALUE
numeric_denominator(VALUE self)
{
    return f_denominator(f_to_r(self));
}
            
div(numeric) => integer click to toggle source

Uses / to perform division, then converts the result to an integer. Numeric does not define the / operator; this is left to subclasses.

 
               static VALUE
num_div(VALUE x, VALUE y)
{
    if (rb_equal(INT2FIX(0), y)) rb_num_zerodiv();
    return num_floor(rb_funcall(x, '/', 1, y));
}
            
divmod( aNumeric ) → anArray click to toggle source

Returns an array containing the quotient and modulus obtained by dividing num by aNumeric. If q, r = x.divmod(y), then

q = floor(float(x)/float(y))
x = q*y + r

The quotient is rounded toward -infinity, as shown in the following table:

 a    |  b  |  a.divmod(b)  |   a/b   | a.modulo(b) | a.remainder(b)
------+-----+---------------+---------+-------------+---------------
 13   |  4  |   3,    1     |   3     |    1        |     1
------+-----+---------------+---------+-------------+---------------
 13   | -4  |  -4,   -3     |  -3     |   -3        |     1
------+-----+---------------+---------+-------------+---------------
-13   |  4  |  -4,    3     |  -4     |    3        |    -1
------+-----+---------------+---------+-------------+---------------
-13   | -4  |   3,   -1     |   3     |   -1        |    -1
------+-----+---------------+---------+-------------+---------------
 11.5 |  4  |   2,    3.5   |   2.875 |    3.5      |     3.5
------+-----+---------------+---------+-------------+---------------
 11.5 | -4  |  -3,   -0.5   |  -2.875 |   -0.5      |     3.5
------+-----+---------------+---------+-------------+---------------
-11.5 |  4  |  -3,    0.5   |  -2.875 |    0.5      |    -3.5
------+-----+---------------+---------+-------------+---------------
-11.5 | -4  |   2,   -3.5   |   2.875 |   -3.5      |    -3.5

Examples

11.divmod(3)         #=> [3, 2]
11.divmod(-3)        #=> [-4, -1]
11.divmod(3.5)       #=> [3, 0.5]
(-11).divmod(3.5)    #=> [-4, 3.0]
(11.5).divmod(3.5)   #=> [3, 1.0]
 
               static VALUE
num_divmod(VALUE x, VALUE y)
{
    return rb_assoc_new(num_div(x, y), rb_funcall(x, '%', 1, y));
}
            
eql?(numeric) => true or false click to toggle source

Returns true if num and numeric are the same type and have equal values.

1 == 1.0          #=> true
1.eql?(1.0)       #=> false
(1.0).eql?(1.0)   #=> true
 
               static VALUE
num_eql(VALUE x, VALUE y)
{
    if (TYPE(x) != TYPE(y)) return Qfalse;

    return rb_equal(x, y);
}
            
fdiv(numeric) => float click to toggle source

Returns float division.

 
               static VALUE
num_fdiv(VALUE x, VALUE y)
{
    return rb_funcall(rb_Float(x), '/', 1, y);
}
            
floor => integer click to toggle source

Returns the largest integer less than or equal to num. Numeric implements this by converting anInteger to a Float and invoking Float#floor.

1.floor      #=> 1
(-1).floor   #=> -1
 
               static VALUE
num_floor(VALUE num)
{
    return flo_floor(rb_Float(num));
}
            
imag() click to toggle source
 
               static VALUE
numeric_imag(VALUE self)
{
    return INT2FIX(0);
}
            
imaginary() click to toggle source
 
               static VALUE
numeric_imag(VALUE self)
{
    return INT2FIX(0);
}
            
integer? → true or false click to toggle source

Returns true if num is an Integer (including Fixnum and Bignum).

 
               static VALUE
num_int_p(VALUE num)
{
    return Qfalse;
}
            
abs => num or numeric click to toggle source

Returns the absolute value of num.

12.abs         #=> 12
(-34.56).abs   #=> 34.56
-34.56.abs     #=> 34.56
 
               static VALUE
num_abs(VALUE num)
{
    if (RTEST(rb_funcall(num, '<', 1, INT2FIX(0)))) {
        return rb_funcall(num, rb_intern("-@"), 0);
    }
    return num;
}
            
modulo(numeric) => result click to toggle source

Equivalent to num.divmod(aNumeric).

 
               static VALUE
num_modulo(VALUE x, VALUE y)
{
    return rb_funcall(x, '%', 1, y);
}
            
nonzero? => num or nil click to toggle source

Returns num if num is not zero, nil otherwise. This behavior is useful when chaining comparisons:

a = %w( z Bb bB bb BB a aA Aa AA A )
b = a.sort {|a,b| (a.downcase <=> b.downcase).nonzero? || a <=> b }
b   #=> ["A", "a", "AA", "Aa", "aA", "BB", "Bb", "bB", "bb", "z"]
 
               static VALUE
num_nonzero_p(VALUE num)
{
    if (RTEST(rb_funcall(num, rb_intern("zero?"), 0, 0))) {
        return Qnil;
    }
    return num;
}
            
numerator() click to toggle source
 
               static VALUE
numeric_numerator(VALUE self)
{
    return f_numerator(f_to_r(self));
}
            
phase → 0 or float click to toggle source

Returns 0 if the value is positive, pi otherwise.

 
               static VALUE
numeric_arg(VALUE self)
{
    if (f_positive_p(self))
        return INT2FIX(0);
    return rb_const_get(rb_mMath, id_PI);
}
            
polar() click to toggle source
 
               static VALUE
numeric_polar(VALUE self)
{
    return rb_assoc_new(f_abs(self), f_arg(self));
}
            
quo(numeric) => result click to toggle source

Returns most exact division (rational for integers, float for floats).

 
               static VALUE
num_quo(VALUE x, VALUE y)
{
    return rb_funcall(rb_rational_raw1(x), '/', 1, y);
}
            
real() click to toggle source

 
               static VALUE
numeric_real(VALUE self)
{
    return self;
}
            
real? → true or false click to toggle source

Returns true if num is a Real (i.e. non Complex).

 
               static VALUE
num_real_p(VALUE num)
{
    return Qtrue;
}
            
rect() click to toggle source
 
               static VALUE
numeric_rect(VALUE self)
{
    return rb_assoc_new(self, INT2FIX(0));
}
            
rectangular() click to toggle source
 
               static VALUE
numeric_rect(VALUE self)
{
    return rb_assoc_new(self, INT2FIX(0));
}
            
remainder(numeric) => result click to toggle source

If num and numeric have different signs, returns mod-numeric; otherwise, returns mod. In both cases mod is the value num.modulo(numeric). The differences between remainder and modulo (%) are shown in the table under Numeric#divmod.

 
               static VALUE
num_remainder(VALUE x, VALUE y)
{
    VALUE z = rb_funcall(x, '%', 1, y);

    if ((!rb_equal(z, INT2FIX(0))) &&
        ((RTEST(rb_funcall(x, '<', 1, INT2FIX(0))) &&
          RTEST(rb_funcall(y, '>', 1, INT2FIX(0)))) ||
         (RTEST(rb_funcall(x, '>', 1, INT2FIX(0))) &&
          RTEST(rb_funcall(y, '<', 1, INT2FIX(0)))))) {
        return rb_funcall(z, '-', 1, y);
    }
    return z;
}
            
round([ndigits]) => integer or float click to toggle source

Rounds num to a given precision in decimal digits (default 0 digits). Precision may be negative. Returns a a floating point number when ndigits is more than one. Numeric implements this by converting itself to a Float and invoking Float#round.

 
               static VALUE
num_round(int argc, VALUE* argv, VALUE num)
{
    return flo_round(argc, argv, rb_Float(num));
}
            
singleton_method_added(p1) click to toggle source

Trap attempts to add methods to Numeric objects. Always raises a TypeError

 
               static VALUE
num_sadded(VALUE x, VALUE name)
{
    ID mid = rb_to_id(name);
    /* ruby_frame = ruby_frame->prev; */ /* pop frame for "singleton_method_added" */
    /* Numerics should be values; singleton_methods should not be added to them */
    rb_remove_method_id(rb_singleton_class(x), mid);
    rb_raise(rb_eTypeError,
             "can't define singleton method \"%s\" for %s",
             rb_id2name(mid),
             rb_obj_classname(x));
    return Qnil;                /* not reached */
}
            
step(limit, step ) {|i| block } => num click to toggle source

Invokes block with the sequence of numbers starting at num, incremented by step on each call. The loop finishes when the value to be passed to the block is greater than limit (if step is positive) or less than limit (if step is negative). If all the arguments are integers, the loop operates using an integer counter. If any of the arguments are floating point numbers, all are converted to floats, and the loop is executed floor(n + n*epsilon)+ 1 times, where n = (limit - num)/step. Otherwise, the loop starts at num, uses either the < or > operator to compare the counter against limit, and increments itself using the + operator.

1.step(10, 2) { |i| print i, " " }
Math::E.step(Math::PI, 0.2) { |f| print f, " " }

produces:

1 3 5 7 9
2.71828182845905 2.91828182845905 3.11828182845905
 
               static VALUE
num_step(int argc, VALUE *argv, VALUE from)
{
    VALUE to, step;

    RETURN_ENUMERATOR(from, argc, argv);
    if (argc == 1) {
        to = argv[0];
        step = INT2FIX(1);
    }
    else {
        if (argc == 2) {
            to = argv[0];
            step = argv[1];
        }
        else {
            rb_raise(rb_eArgError, "wrong number of arguments");
        }
        if (rb_equal(step, INT2FIX(0))) {
            rb_raise(rb_eArgError, "step can't be 0");
        }
    }

    if (FIXNUM_P(from) && FIXNUM_P(to) && FIXNUM_P(step)) {
        long i, end, diff;

        i = FIX2LONG(from);
        end = FIX2LONG(to);
        diff = FIX2LONG(step);

        if (diff > 0) {
            while (i <= end) {
                rb_yield(LONG2FIX(i));
                i += diff;
            }
        }
        else {
            while (i >= end) {
                rb_yield(LONG2FIX(i));
                i += diff;
            }
        }
    }
    else if (!ruby_float_step(from, to, step, Qfalse)) {
        VALUE i = from;
        ID cmp;

        if (RTEST(rb_funcall(step, '>', 1, INT2FIX(0)))) {
            cmp = '>';
        }
        else {
            cmp = '<';
        }
        for (;;) {
            if (RTEST(rb_funcall(i, cmp, 1, to))) break;
            rb_yield(i);
            i = rb_funcall(i, '+', 1, step);
        }
    }
    return from;
}
            
to_c() click to toggle source
 
               static VALUE
numeric_to_c(VALUE self)
{
    return rb_complex_new1(self);
}
            
to_int => integer click to toggle source

Invokes the child class’s to_i method to convert num to an integer.

 
               static VALUE
num_to_int(VALUE num)
{
    return rb_funcall(num, id_to_i, 0, 0);
}
            
truncate => integer click to toggle source

Returns num truncated to an integer. Numeric implements this by converting its value to a float and invoking Float#truncate.

 
               static VALUE
num_truncate(VALUE num)
{
    return flo_truncate(rb_Float(num));
}
            
zero? => true or false click to toggle source

Returns true if num has a zero value.

 
               static VALUE
num_zero_p(VALUE num)
{
    if (rb_equal(num, INT2FIX(0))) {
        return Qtrue;
    }
    return Qfalse;
}
            

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