Class: Numeric

Inherits:
Object show all
Includes:
Comparable
Defined in:
numeric.c

Direct Known Subclasses

Float, Integer

Instance Method Summary collapse

Methods included from Comparable

#<, #<=, #==, #>, #>=, #between?

Instance Method Details

#+ ⇒ Numeric

Unary Plus---Returns the receiver's value.

Returns:




# File 'numeric.c'

static VALUE
num_uplus(num)
    VALUE num;
{
    return num;
}

#- ⇒ Numeric

Unary Minus---Returns the receiver's value, negated.

Returns:




# File 'numeric.c'

static VALUE
num_uminus(num)
    VALUE num;
{
    VALUE zero;

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

    return rb_funcall(zero, '-', 1, num);
}

#<=>(other) ⇒ 0?

Returns zero if num equals other, nil otherwise.

Returns:

  • (0, nil) 



# File 'numeric.c'

static VALUE
num_cmp(x, y)
    VALUE x, y;
{
    if (x == y) return INT2FIX(0);
    return Qnil;
}

#abs ⇒ Numeric

Returns the absolute value of num.

12.abs         #=> 12
(-34.56).abs   #=> 34.56
-34.56.abs     #=> 34.56

Returns:




# File 'numeric.c'

static VALUE
num_abs(num)
VALUE num;
{
if (RTEST(rb_funcall(num, '<', 1, INT2FIX(0)))) {
return rb_funcall(num, rb_intern("-@"), 0);
}

#ceil ⇒ Integer

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

Returns:




# File 'numeric.c'

static VALUE
num_ceil(num)
    VALUE num;
{
    return flo_ceil(rb_Float(num));
}

#coerce(numeric) ⇒ Array

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]

Returns:




# File 'numeric.c'

static VALUE
num_coerce(x, y)
    VALUE x, 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);
}

#div(numeric) ⇒ Integer

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

Returns:




# File 'numeric.c'

static VALUE
num_div(x, y)
    VALUE x, y;
{
    return num_floor(rb_funcall(x, '/', 1, y));
}

#divmod(aNumeric) ⇒ Array

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]

Returns:




# File 'numeric.c'

static VALUE
num_divmod(x, y)
    VALUE x, y;
{
    return rb_assoc_new(num_div(x, y), rb_funcall(x, '%', 1, y));
}

#eql?(numeric) ⇒ Boolean

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

Returns:

  • (Boolean) 



# File 'numeric.c'

static VALUE
num_eql(x, y)
    VALUE x, y;
{
    if (TYPE(x) != TYPE(y)) return Qfalse;

    return rb_equal(x, y);
}

#floor ⇒ Integer

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

Returns:




# File 'numeric.c'

static VALUE
num_floor(num)
    VALUE num;
{
    return flo_floor(rb_Float(num));
}

#initialize_copy ⇒ Object

:nodoc:




# File 'numeric.c'

static VALUE
num_init_copy(x, y)
    VALUE x, y;
{
    /* Numerics are immutable values, which should not be copied */
    rb_raise(rb_eTypeError, "can't copy %s", rb_obj_classname(x));
    return Qnil;        /* not reached */
}

#integer? ⇒ Boolean

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

Returns:

  • (Boolean) 



# File 'numeric.c'

static VALUE
num_int_p(num)
    VALUE num;
{
    return Qfalse;
}

#modulo(numeric) ⇒ Object

Equivalent to num.divmod(aNumeric)[1].




# File 'numeric.c'

static VALUE
num_modulo(x, y)
    VALUE x, y;
{
    return rb_funcall(x, '%', 1, y);
}

#nonzero? ⇒ Numeric?

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"]

Returns:




# File 'numeric.c'

static VALUE
num_nonzero_p(num)
VALUE num;
{
if (RTEST(rb_funcall(num, rb_intern("zero?"), 0, 0))) {
return Qnil;
}

#quo(numeric) ⇒ Object

Equivalent to Numeric#/, but overridden in subclasses.




# File 'numeric.c'

static VALUE
num_quo(x, y)
    VALUE x, y;
{
    return rb_funcall(x, '/', 1, y);
}

#remainder(numeric) ⇒ Object

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.




# File 'numeric.c'

static VALUE
num_remainder(x, y)
VALUE x, 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);
}

#round ⇒ Integer

Rounds num to the nearest integer. Numeric implements this by converting itself to a Float and invoking Float#round.

Returns:




# File 'numeric.c'

static VALUE
num_round(num)
    VALUE num;
{
    return flo_round(rb_Float(num));
}

#singleton_method_added ⇒ Object

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




# File 'numeric.c'

static VALUE
num_sadded(x, name)
    VALUE x, 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_raise(rb_eTypeError,
         "can't define singleton method \"%s\" for %s",
         rb_id2name(rb_to_id(name)),
         rb_obj_classname(x)); 
    return Qnil;        /* not reached */
}

#step(limit, step) {|i| ... } ⇒ Numeric

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

Yields:

  • (i)

Returns:




# File 'numeric.c'

static VALUE
num_step(argc, argv, from)
int argc;
VALUE *argv;
VALUE from;
{
VALUE to, step;

if (argc == 1) {
to = argv[0];
step = INT2FIX(1);
}

#to_int ⇒ Integer

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

Returns:




# File 'numeric.c'

static VALUE
num_to_int(num)
    VALUE num;
{
    return rb_funcall(num, id_to_i, 0, 0);
}

#truncate ⇒ Integer

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

Returns:




# File 'numeric.c'

static VALUE
num_truncate(num)
    VALUE num;
{
    return flo_truncate(rb_Float(num));
}

#zero? ⇒ Boolean

Returns true if num has a zero value.

Returns:

  • (Boolean) 



# File 'numeric.c'

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