Class | Numeric |
In: |
numeric.c
lib/complex.rb |
Parent: | Object |
Unary Plus—Returns the receiver‘s value.
/* * call-seq: * +num => num * * Unary Plus---Returns the receiver's value. */ static VALUE num_uplus(num) VALUE num; { return num; }
Unary Minus—Returns the receiver‘s value, negated.
/* * call-seq: * -num => numeric * * Unary Minus---Returns the receiver's value, negated. */ static VALUE num_uminus(num) VALUE num; { VALUE zero; zero = INT2FIX(0); do_coerce(&zero, &num, Qtrue); return rb_funcall(zero, '-', 1, num); }
Returns zero if num equals other, nil otherwise.
/* * call-seq: * num <=> other -> 0 or nil * * Returns zero if <i>num</i> equals <i>other</i>, <code>nil</code> * otherwise. */ static VALUE num_cmp(x, y) VALUE x, y; { if (x == y) return INT2FIX(0); return Qnil; }
Returns the absolute value of num.
12.abs #=> 12 (-34.56).abs #=> 34.56 -34.56.abs #=> 34.56
/* * call-seq: * num.abs => num or numeric * * Returns the absolute value of <i>num</i>. * * 12.abs #=> 12 * (-34.56).abs #=> 34.56 * -34.56.abs #=> 34.56 */ static VALUE num_abs(num) VALUE num; { if (RTEST(rb_funcall(num, '<', 1, INT2FIX(0)))) { return rb_funcall(num, rb_intern("-@"), 0); } return num; }
See Complex#arg.
# File lib/complex.rb, line 60 def arg if self >= 0 return 0 else return Math::PI end end
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
/* * call-seq: * num.ceil => integer * * Returns the smallest <code>Integer</code> greater than or equal to * <i>num</i>. Class <code>Numeric</code> achieves this by converting * itself to a <code>Float</code> then invoking * <code>Float#ceil</code>. * * 1.ceil #=> 1 * 1.2.ceil #=> 2 * (-1.2).ceil #=> -1 * (-1.0).ceil #=> -1 */ static VALUE num_ceil(num) VALUE num; { return flo_ceil(rb_Float(num)); }
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]
/* * call-seq: * num.coerce(numeric) => array * * If <i>aNumeric</i> is the same type as <i>num</i>, returns an array * containing <i>aNumeric</i> and <i>num</i>. Otherwise, returns an * array with both <i>aNumeric</i> and <i>num</i> represented as * <code>Float</code> 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(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); }
See Complex#conjugate (short answer: returns self).
# File lib/complex.rb, line 79 def conjugate self end
Uses / to perform division, then converts the result to an integer. Numeric does not define the / operator; this is left to subclasses.
/* * call-seq: * num.div(numeric) => integer * * Uses <code>/</code> to perform division, then converts the result to * an integer. <code>Numeric</code> does not define the <code>/</code> * operator; this is left to subclasses. */ static VALUE num_div(x, y) VALUE x, y; { return num_floor(rb_funcall(x, '/', 1, y)); }
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]
/* * call-seq: * num.divmod( aNumeric ) -> anArray * * Returns an array containing the quotient and modulus obtained by * dividing <i>num</i> by <i>aNumeric</i>. If <code>q, r = * x.divmod(y)</code>, 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(x, y) VALUE x, y; { return rb_assoc_new(num_div(x, y), rb_funcall(x, '%', 1, y)); }
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
/* * call-seq: * num.eql?(numeric) => true or false * * Returns <code>true</code> if <i>num</i> and <i>numeric</i> 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(x, y) VALUE x, y; { if (TYPE(x) != TYPE(y)) return Qfalse; return rb_equal(x, y); }
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
/* * call-seq: * num.floor => integer * * Returns the largest integer less than or equal to <i>num</i>. * <code>Numeric</code> implements this by converting <i>anInteger</i> * to a <code>Float</code> and invoking <code>Float#floor</code>. * * 1.floor #=> 1 * (-1).floor #=> -1 */ static VALUE num_floor(num) VALUE num; { return flo_floor(rb_Float(num)); }
Returns true if num is an Integer (including Fixnum and Bignum).
/* * call-seq: * num.integer? -> true or false * * Returns <code>true</code> if <i>num</i> is an <code>Integer</code> * (including <code>Fixnum</code> and <code>Bignum</code>). */ static VALUE num_int_p(num) VALUE num; { return Qfalse; }
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"]
/* * call-seq: * num.nonzero? => num or nil * * Returns <i>num</i> if <i>num</i> is not zero, <code>nil</code> * 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(num) VALUE num; { if (RTEST(rb_funcall(num, rb_intern("zero?"), 0, 0))) { return Qnil; } return num; }
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.
/* * call-seq: * num.remainder(numeric) => result * * If <i>num</i> and <i>numeric</i> have different signs, returns * <em>mod</em>-<i>numeric</i>; otherwise, returns <em>mod</em>. In * both cases <em>mod</em> is the value * <i>num</i>.<code>modulo(</code><i>numeric</i><code>)</code>. The * differences between <code>remainder</code> and modulo * (<code>%</code>) are shown in the table under <code>Numeric#divmod</code>. */ 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); } return z; }
Rounds num to the nearest integer. Numeric implements this by converting itself to a Float and invoking Float#round.
/* * call-seq: * num.round => integer * * Rounds <i>num</i> to the nearest integer. <code>Numeric</code> * implements this by converting itself to a * <code>Float</code> and invoking <code>Float#round</code>. */ static VALUE num_round(num) VALUE num; { return flo_round(rb_Float(num)); }
Trap attempts to add methods to Numeric objects. Always raises a TypeError
/* * Trap attempts to add methods to <code>Numeric</code> objects. Always * raises a <code>TypeError</code> */ 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 */ }
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
/* * call-seq: * num.step(limit, step ) {|i| block } => num * * Invokes <em>block</em> with the sequence of numbers starting at * <i>num</i>, incremented by <i>step</i> on each call. The loop * finishes when the value to be passed to the block is greater than * <i>limit</i> (if <i>step</i> is positive) or less than * <i>limit</i> (if <i>step</i> 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 <i>floor(n + n*epsilon)+ 1</i> times, * where <i>n = (limit - num)/step</i>. Otherwise, the loop * starts at <i>num</i>, uses either the <code><</code> or * <code>></code> operator to compare the counter against * <i>limit</i>, and increments itself using the <code>+</code> * operator. * * 1.step(10, 2) { |i| print i, " " } * Math::E.step(Math::PI, 0.2) { |f| print f, " " } * * <em>produces:</em> * * 1 3 5 7 9 * 2.71828182845905 2.91828182845905 3.11828182845905 */ static VALUE num_step(argc, argv, from) 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 (TYPE(from) == T_FLOAT || TYPE(to) == T_FLOAT || TYPE(step) == T_FLOAT) { const double epsilon = DBL_EPSILON; double beg = NUM2DBL(from); double end = NUM2DBL(to); double unit = NUM2DBL(step); double n = (end - beg)/unit; double err = (fabs(beg) + fabs(end) + fabs(end-beg)) / fabs(unit) * epsilon; long i; if (err>0.5) err=0.5; n = floor(n + err) + 1; for (i=0; i<n; i++) { rb_yield(rb_float_new(i*unit+beg)); } } else { 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; }
Invokes the child class‘s to_i method to convert num to an integer.
/* * call-seq: * num.to_int => integer * * Invokes the child class's <code>to_i</code> method to convert * <i>num</i> to an integer. */ static VALUE num_to_int(num) VALUE num; { return rb_funcall(num, id_to_i, 0, 0); }
Returns num truncated to an integer. Numeric implements this by converting its value to a float and invoking Float#truncate.
/* * call-seq: * num.truncate => integer * * Returns <i>num</i> truncated to an integer. <code>Numeric</code> * implements this by converting its value to a float and invoking * <code>Float#truncate</code>. */ static VALUE num_truncate(num) VALUE num; { return flo_truncate(rb_Float(num)); }