A Complex object houses a pair of values, given when the object is created as either rectangular coordinates or polar coordinates.
Rectangular Coordinates¶ ↑The rectangular coordinates of a complex number are called the real and imaginary parts; see Complex number definition.
You can create a Complex object from rectangular coordinates with:
Method Complex.rect
.
Method Kernel#Complex
, either with numeric arguments or with certain string arguments.
Method String#to_c
, for certain strings.
Note that each of the stored parts may be a an instance one of the classes Complex
, Float
, Integer
, or Rational
; they may be retrieved:
Separately, with methods Complex#real
and Complex#imaginary
.
Together, with method Complex#rect
.
The corresponding (computed) polar values may be retrieved:
Separately, with methods Complex#abs
and Complex#arg
.
Together, with method Complex#polar
.
The polar coordinates of a complex number are called the absolute and argument parts; see Complex polar plane.
In this class, the argument part in expressed radians (not degrees).
You can create a Complex object from polar coordinates with:
Method Complex.polar
.
Method Kernel#Complex
, with certain string arguments.
Method String#to_c
, for certain strings.
Note that each of the stored parts may be a an instance one of the classes Complex
, Float
, Integer
, or Rational
; they may be retrieved:
Separately, with methods Complex#abs
and Complex#arg
.
Together, with method Complex#polar
.
The corresponding (computed) rectangular values may be retrieved:
Separately, with methods Complex#real
and Complex#imag
.
Together, with method Complex#rect
.
First, whatâs elsewhere:
Class Complex inherits (directly or indirectly) from classes Numeric and Object.
Includes (indirectly) module Comparable.
Here, class Complex has methods for:
Creating Complex Objects¶ ↑::polar
: Returns a new Complex object based on given polar coordinates.
::rect
(and its alias ::rectangular
): Returns a new Complex object based on given rectangular coordinates.
abs
(and its alias magnitude
): Returns the absolute value for self
.
arg
(and its aliases angle
and phase
): Returns the argument (angle) for self
in radians.
denominator
: Returns the denominator of self
.
finite?
: Returns whether both self.real
and self.image
are finite.
hash
: Returns the integer hash value for self
.
imag
(and its alias imaginary
): Returns the imaginary value for self
.
infinite?
: Returns whether self.real
or self.image
is infinite.
numerator
: Returns the numerator of self
.
polar
: Returns the array [self.abs, self.arg]
.
inspect
: Returns a string representation of self
.
real
: Returns the real value for self
.
real?
: Returns false
; for compatibility with Numeric#real?
.
rect
(and its alias rectangular
): Returns the array [self.real, self.imag]
.
<=>
: Returns whether self
is less than, equal to, or greater than the given argument.
==
: Returns whether self
is equal to the given argument.
rationalize
: Returns a Rational
object whose value is exactly or approximately equivalent to that of self.real
.
to_c
: Returns self
.
to_d: Returns the value as a BigDecimal
object.
to_f
: Returns the value of self.real
as a Float
, if possible.
to_i
: Returns the value of self.real
as an Integer
, if possible.
to_r
: Returns the value of self.real
as a Rational
, if possible.
to_s
: Returns a string representation of self
.
Complex
Arithmetic¶ ↑
*
: Returns the product of self
and the given numeric.
**
: Returns self
raised to power of the given numeric.
+
: Returns the sum of self
and the given numeric.
-
: Returns the difference of self
and the given numeric.
-@
: Returns the negation of self
.
/
: Returns the quotient of self
and the given numeric.
abs2
: Returns square of the absolute value (magnitude) for self
.
conj
(and its alias conjugate
): Returns the conjugate of self
.
fdiv
: Returns Complex.rect(self.real/numeric, self.imag/numeric)
.
JSON
¶ ↑
::json_create
: Returns a new Complex object, deserialized from the given serialized hash.
as_json
: Returns a serialized hash constructed from self
.
These methods are provided by the JSON gem. To make these methods available:
require 'json/add/complex'Constants
Equivalent to Complex.rect(0, 1)
:
Complex::I
def self.json_create(object) Complex(object['r'], object['i']) end
See as_json
.
static VALUE nucomp_s_polar(int argc, VALUE *argv, VALUE klass) { VALUE abs, arg; argc = rb_scan_args(argc, argv, "11", &abs, &arg); abs = nucomp_real_check(abs); if (argc == 2) { arg = nucomp_real_check(arg); } else { arg = ZERO; } return f_complex_polar_real(klass, abs, arg); }
Returns a new Complex object formed from the arguments, each of which must be an instance of Numeric
, or an instance of one of its subclasses: Complex, Float
, Integer
, Rational
. Argument arg
is given in radians; see Polar Coordinates:
Complex.polar(3) Complex.polar(3, 2.0) Complex.polar(-3, -2.0)Source
static VALUE nucomp_s_new(int argc, VALUE *argv, VALUE klass) { VALUE real, imag; switch (rb_scan_args(argc, argv, "11", &real, &imag)) { case 1: real = nucomp_real_check(real); imag = ZERO; break; default: real = nucomp_real_check(real); imag = nucomp_real_check(imag); break; } return nucomp_s_new_internal(klass, real, imag); }
Returns a new Complex object formed from the arguments, each of which must be an instance of Numeric
, or an instance of one of its subclasses: Complex, Float
, Integer
, Rational
; see Rectangular Coordinates:
Complex.rect(3) Complex.rect(3, Math::PI) Complex.rect(-3, -Math::PI)
Complex.rectangular is an alias for Complex.rect.
Sourcestatic VALUE nucomp_s_new(int argc, VALUE *argv, VALUE klass) { VALUE real, imag; switch (rb_scan_args(argc, argv, "11", &real, &imag)) { case 1: real = nucomp_real_check(real); imag = ZERO; break; default: real = nucomp_real_check(real); imag = nucomp_real_check(imag); break; } return nucomp_s_new_internal(klass, real, imag); }
Returns a new Complex object formed from the arguments, each of which must be an instance of Numeric
, or an instance of one of its subclasses: Complex, Float
, Integer
, Rational
; see Rectangular Coordinates:
Complex.rect(3) Complex.rect(3, Math::PI) Complex.rect(-3, -Math::PI)
Complex.rectangular is an alias for Complex.rect.
Public Instance Methods SourceVALUE rb_complex_mul(VALUE self, VALUE other) { if (RB_TYPE_P(other, T_COMPLEX)) { VALUE real, imag; get_dat2(self, other); comp_mul(adat->real, adat->imag, bdat->real, bdat->imag, &real, &imag); return f_complex_new2(CLASS_OF(self), real, imag); } if (k_numeric_p(other) && f_real_p(other)) { get_dat1(self); return f_complex_new2(CLASS_OF(self), f_mul(dat->real, other), f_mul(dat->imag, other)); } return rb_num_coerce_bin(self, other, '*'); }
Returns the product of self
and numeric
:
Complex.rect(2, 3) * Complex.rect(2, 3) Complex.rect(900) * Complex.rect(1) Complex.rect(-2, 9) * Complex.rect(-9, 2) Complex.rect(9, 8) * 4 Complex.rect(20, 9) * 9.8Source
VALUE rb_complex_pow(VALUE self, VALUE other) { if (k_numeric_p(other) && k_exact_zero_p(other)) return f_complex_new_bang1(CLASS_OF(self), ONE); if (RB_TYPE_P(other, T_RATIONAL) && RRATIONAL(other)->den == LONG2FIX(1)) other = RRATIONAL(other)->num; /* c14n */ if (RB_TYPE_P(other, T_COMPLEX)) { get_dat1(other); if (k_exact_zero_p(dat->imag)) other = dat->real; /* c14n */ } if (other == ONE) { get_dat1(self); return nucomp_s_new_internal(CLASS_OF(self), dat->real, dat->imag); } VALUE result = complex_pow_for_special_angle(self, other); if (!UNDEF_P(result)) return result; if (RB_TYPE_P(other, T_COMPLEX)) { VALUE r, theta, nr, ntheta; get_dat1(other); r = f_abs(self); theta = f_arg(self); nr = m_exp_bang(f_sub(f_mul(dat->real, m_log_bang(r)), f_mul(dat->imag, theta))); ntheta = f_add(f_mul(theta, dat->real), f_mul(dat->imag, m_log_bang(r))); return f_complex_polar(CLASS_OF(self), nr, ntheta); } if (FIXNUM_P(other)) { long n = FIX2LONG(other); if (n == 0) { return nucomp_s_new_internal(CLASS_OF(self), ONE, ZERO); } if (n < 0) { self = f_reciprocal(self); other = rb_int_uminus(other); n = -n; } { get_dat1(self); VALUE xr = dat->real, xi = dat->imag, zr = xr, zi = xi; if (f_zero_p(xi)) { zr = rb_num_pow(zr, other); } else if (f_zero_p(xr)) { zi = rb_num_pow(zi, other); if (n & 2) zi = f_negate(zi); if (!(n & 1)) { VALUE tmp = zr; zr = zi; zi = tmp; } } else { while (--n) { long q, r; for (; q = n / 2, r = n % 2, r == 0; n = q) { VALUE tmp = f_sub(f_mul(xr, xr), f_mul(xi, xi)); xi = f_mul(f_mul(TWO, xr), xi); xr = tmp; } comp_mul(zr, zi, xr, xi, &zr, &zi); } } return nucomp_s_new_internal(CLASS_OF(self), zr, zi); } } if (k_numeric_p(other) && f_real_p(other)) { VALUE r, theta; if (RB_BIGNUM_TYPE_P(other)) rb_warn("in a**b, b may be too big"); r = f_abs(self); theta = f_arg(self); return f_complex_polar(CLASS_OF(self), f_expt(r, other), f_mul(theta, other)); } return rb_num_coerce_bin(self, other, id_expt); }
Returns self
raised to power numeric
:
Complex.rect(0, 1) ** 2 Complex.rect(-8) ** Rational(1, 3)Source
VALUE rb_complex_plus(VALUE self, VALUE other) { if (RB_TYPE_P(other, T_COMPLEX)) { VALUE real, imag; get_dat2(self, other); real = f_add(adat->real, bdat->real); imag = f_add(adat->imag, bdat->imag); return f_complex_new2(CLASS_OF(self), real, imag); } if (k_numeric_p(other) && f_real_p(other)) { get_dat1(self); return f_complex_new2(CLASS_OF(self), f_add(dat->real, other), dat->imag); } return rb_num_coerce_bin(self, other, '+'); }
Returns the sum of self
and numeric
:
Complex.rect(2, 3) + Complex.rect(2, 3) Complex.rect(900) + Complex.rect(1) Complex.rect(-2, 9) + Complex.rect(-9, 2) Complex.rect(9, 8) + 4 Complex.rect(20, 9) + 9.8Source
VALUE rb_complex_minus(VALUE self, VALUE other) { if (RB_TYPE_P(other, T_COMPLEX)) { VALUE real, imag; get_dat2(self, other); real = f_sub(adat->real, bdat->real); imag = f_sub(adat->imag, bdat->imag); return f_complex_new2(CLASS_OF(self), real, imag); } if (k_numeric_p(other) && f_real_p(other)) { get_dat1(self); return f_complex_new2(CLASS_OF(self), f_sub(dat->real, other), dat->imag); } return rb_num_coerce_bin(self, other, '-'); }
Returns the difference of self
and numeric
:
Complex.rect(2, 3) - Complex.rect(2, 3) Complex.rect(900) - Complex.rect(1) Complex.rect(-2, 9) - Complex.rect(-9, 2) Complex.rect(9, 8) - 4 Complex.rect(20, 9) - 9.8Source
VALUE rb_complex_uminus(VALUE self) { get_dat1(self); return f_complex_new2(CLASS_OF(self), f_negate(dat->real), f_negate(dat->imag)); }
Returns the negation of self
, which is the negation of each of its parts:
-Complex.rect(1, 2) -Complex.rect(-1, -2)Source
VALUE rb_complex_div(VALUE self, VALUE other) { return f_divide(self, other, f_quo, id_quo); }
Returns the quotient of self
and numeric
:
Complex.rect(2, 3) / Complex.rect(2, 3) Complex.rect(900) / Complex.rect(1) Complex.rect(-2, 9) / Complex.rect(-9, 2) Complex.rect(9, 8) / 4 Complex.rect(20, 9) / 9.8Source
static VALUE nucomp_cmp(VALUE self, VALUE other) { if (!k_numeric_p(other)) { return rb_num_coerce_cmp(self, other, idCmp); } if (!nucomp_real_p(self)) { return Qnil; } if (RB_TYPE_P(other, T_COMPLEX)) { if (nucomp_real_p(other)) { get_dat2(self, other); return rb_funcall(adat->real, idCmp, 1, bdat->real); } } else { get_dat1(self); if (f_real_p(other)) { return rb_funcall(dat->real, idCmp, 1, other); } else { return rb_num_coerce_cmp(dat->real, other, idCmp); } } return Qnil; }
Returns:
self.real <=> object.real
if both of the following are true:
self.imag == 0
.
object.imag == 0
. # Always true if object is numeric but not complex.
nil
otherwise.
Examples:
Complex.rect(2) <=> 3 Complex.rect(2) <=> 2 Complex.rect(2) <=> 1 Complex.rect(2, 1) <=> 1 Complex.rect(1) <=> Complex.rect(1, 1) Complex.rect(1) <=> 'Foo'Source
static VALUE nucomp_eqeq_p(VALUE self, VALUE other) { if (RB_TYPE_P(other, T_COMPLEX)) { get_dat2(self, other); return RBOOL(f_eqeq_p(adat->real, bdat->real) && f_eqeq_p(adat->imag, bdat->imag)); } if (k_numeric_p(other) && f_real_p(other)) { get_dat1(self); return RBOOL(f_eqeq_p(dat->real, other) && f_zero_p(dat->imag)); } return RBOOL(f_eqeq_p(other, self)); }
Returns true
if self.real == object.real
and self.imag == object.imag
:
Complex.rect(2, 3) == Complex.rect(2.0, 3.0)Source
VALUE rb_complex_abs(VALUE self) { get_dat1(self); if (f_zero_p(dat->real)) { VALUE a = f_abs(dat->imag); if (RB_FLOAT_TYPE_P(dat->real) && !RB_FLOAT_TYPE_P(dat->imag)) a = f_to_f(a); return a; } if (f_zero_p(dat->imag)) { VALUE a = f_abs(dat->real); if (!RB_FLOAT_TYPE_P(dat->real) && RB_FLOAT_TYPE_P(dat->imag)) a = f_to_f(a); return a; } return rb_math_hypot(dat->real, dat->imag); }
Returns the absolute value (magnitude) for self
; see polar coordinates:
Complex.polar(-1, 0).abs
If self
was created with rectangular coordinates, the returned value is computed, and may be inexact:
Complex.rectangular(1, 1).absSource
static VALUE nucomp_abs2(VALUE self) { get_dat1(self); return f_add(f_mul(dat->real, dat->real), f_mul(dat->imag, dat->imag)); }
Returns square of the absolute value (magnitude) for self
; see polar coordinates:
Complex.polar(2, 2).abs2
If self
was created with rectangular coordinates, the returned value is computed, and may be inexact:
Complex.rectangular(1.0/3, 1.0/3).abs2Source
VALUE rb_complex_arg(VALUE self) { get_dat1(self); return rb_math_atan2(dat->imag, dat->real); }
Returns the argument (angle) for self
in radians; see polar coordinates:
Complex.polar(3, Math::PI/2).arg
If self
was created with rectangular coordinates, the returned value is computed, and may be inexact:
Complex.polar(1, 1.0/3).argSource
def as_json(*) { JSON.create_id => self.class.name, 'r' => real, 'i' => imag, } end
Methods Complex#as_json
and Complex.json_create
may be used to serialize and deserialize a Complex object; see Marshal
.
Method Complex#as_json
serializes self
, returning a 2-element hash representing self
:
require 'json/add/complex' x = Complex(2).as_json y = Complex(2.0, 4).as_json
Method JSON.create
deserializes such a hash, returning a Complex object:
Complex.json_create(x) Complex.json_create(y)Source
static VALUE nucomp_denominator(VALUE self) { get_dat1(self); return rb_lcm(f_denominator(dat->real), f_denominator(dat->imag)); }
Returns the denominator of self
, which is the least common multiple of self.real.denominator
and self.imag.denominator
:
Complex.rect(Rational(1, 2), Rational(2, 3)).denominator
Note that n.denominator
of a non-rational numeric is 1
.
Related: Complex#numerator
.
static VALUE rb_complex_finite_p(VALUE self) { get_dat1(self); return RBOOL(f_finite_p(dat->real) && f_finite_p(dat->imag)); }
Returns true
if both self.real.finite?
and self.imag.finite?
are true, false
otherwise:
Complex.rect(1, 1).finite? Complex.rect(Float::INFINITY, 0).finite?
Related: Numeric#finite?
, Float#finite?
.
static VALUE nucomp_hash(VALUE self) { return ST2FIX(rb_complex_hash(self)); }
Returns the integer hash value for self
.
Two Complex objects created from the same values will have the same hash value (and will compare using eql?
):
Complex.rect(1, 2).hash == Complex.rect(1, 2).hash
Returns the imaginary value for self
:
Complex.rect(7).imag Complex.rect(9, -4).imag
If self
was created with polar coordinates, the returned value is computed, and may be inexact:
Complex.polar(1, Math::PI/4).imagSource
static VALUE rb_complex_infinite_p(VALUE self) { get_dat1(self); if (!f_infinite_p(dat->real) && !f_infinite_p(dat->imag)) { return Qnil; } return ONE; }
Returns 1
if either self.real.infinite?
or self.imag.infinite?
is true, nil
otherwise:
Complex.rect(Float::INFINITY, 0).infinite? Complex.rect(1, 1).infinite?
Related: Numeric#infinite?
, Float#infinite?
.
static VALUE nucomp_inspect(VALUE self) { VALUE s; s = rb_usascii_str_new2("("); f_format(self, s, rb_inspect); rb_str_cat2(s, ")"); return s; }
Returns a string representation of self
:
Complex.rect(2).inspect Complex.rect(-8, 6).inspect Complex.rect(0, Rational(1, 2)).inspect Complex.rect(0, Float::INFINITY).inspect Complex.rect(Float::NAN, Float::NAN).inspectSource
static VALUE nucomp_numerator(VALUE self) { VALUE cd; get_dat1(self); cd = nucomp_denominator(self); return f_complex_new2(CLASS_OF(self), f_mul(f_numerator(dat->real), f_div(cd, f_denominator(dat->real))), f_mul(f_numerator(dat->imag), f_div(cd, f_denominator(dat->imag)))); }
Returns the Complex object created from the numerators of the real and imaginary parts of self
, after converting each part to the lowest common denominator of the two:
c = Complex.rect(Rational(2, 3), Rational(3, 4)) c.numerator
In this example, the lowest common denominator of the two parts is 12; the two converted parts may be thought of as Rational(8, 12) and Rational(9, 12), whose numerators, respectively, are 8 and 9; so the returned value of c.numerator
is Complex.rect(8, 9)
.
Related: Complex#denominator
.
static VALUE nucomp_polar(VALUE self) { return rb_assoc_new(f_abs(self), f_arg(self)); }
Returns the array [self.abs, self.arg]
:
Complex.polar(1, 2).polar
See Polar Coordinates.
If self
was created with rectangular coordinates, the returned value is computed, and may be inexact:
Complex.rect(1, 1).polarSource
VALUE rb_complex_div(VALUE self, VALUE other) { return f_divide(self, other, f_quo, id_quo); }
Returns the quotient of self
and numeric
:
Complex.rect(2, 3) / Complex.rect(2, 3) Complex.rect(900) / Complex.rect(1) Complex.rect(-2, 9) / Complex.rect(-9, 2) Complex.rect(9, 8) / 4 Complex.rect(20, 9) / 9.8Source
static VALUE nucomp_rationalize(int argc, VALUE *argv, VALUE self) { get_dat1(self); rb_check_arity(argc, 0, 1); if (!k_exact_zero_p(dat->imag)) { rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Rational", self); } return rb_funcallv(dat->real, id_rationalize, argc, argv); }
Returns a Rational
object whose value is exactly or approximately equivalent to that of self.real
.
With no argument epsilon
given, returns a Rational object whose value is exactly equal to that of self.real.rationalize
:
Complex.rect(1, 0).rationalize Complex.rect(1, Rational(0, 1)).rationalize Complex.rect(3.14159, 0).rationalize
With argument epsilon
given, returns a Rational object whose value is exactly or approximately equal to that of self.real
to the given precision:
Complex.rect(3.14159, 0).rationalize(0.1) Complex.rect(3.14159, 0).rationalize(0.01) Complex.rect(3.14159, 0).rationalize(0.001) Complex.rect(3.14159, 0).rationalize(0.0001) Complex.rect(3.14159, 0).rationalize(0.00001) Complex.rect(3.14159, 0).rationalize(0.000001) Complex.rect(3.14159, 0).rationalize(0.0000001) Complex.rect(3.14159, 0).rationalize(0.00000001) Complex.rect(3.14159, 0).rationalize(0.000000001) Complex.rect(3.14159, 0).rationalize(0.0000000001) Complex.rect(3.14159, 0).rationalize(0.0)
Related: Complex#to_r
.
VALUE rb_complex_real(VALUE self) { get_dat1(self); return dat->real; }
Returns the real value for self
:
Complex.rect(7).real Complex.rect(9, -4).real
If self
was created with polar coordinates, the returned value is computed, and may be inexact:
Complex.polar(1, Math::PI/4).realSource
static VALUE nucomp_real_p_m(VALUE self) { return Qfalse; }
Returns false
; for compatibility with Numeric#real?
.
Returns a new Complex object formed from the arguments, each of which must be an instance of Numeric
, or an instance of one of its subclasses: Complex, Float
, Integer
, Rational
; see Rectangular Coordinates:
Complex.rect(3) Complex.rect(3, Math::PI) Complex.rect(-3, -Math::PI)
Complex.rectangular is an alias for Complex.rect.
SourceAlso aliased as:
rect, rect
Sourcestatic VALUE nucomp_to_c(VALUE self) { return self; }
Returns self
.
static VALUE nucomp_to_f(VALUE self) { get_dat1(self); if (!k_exact_zero_p(dat->imag)) { rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Float", self); } return f_to_f(dat->real); }
Returns the value of self.real
as a Float
, if possible:
Complex.rect(1, 0).to_f Complex.rect(1, Rational(0, 1)).to_f
Raises RangeError
if self.imag
is not exactly zero (either Integer(0)
or Rational(0, n)
).
static VALUE nucomp_to_i(VALUE self) { get_dat1(self); if (!k_exact_zero_p(dat->imag)) { rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Integer", self); } return f_to_i(dat->real); }
Returns the value of self.real
as an Integer
, if possible:
Complex.rect(1, 0).to_i Complex.rect(1, Rational(0, 1)).to_i
Raises RangeError
if self.imag
is not exactly zero (either Integer(0)
or Rational(0, n)
).
def to_json(*args) as_json.to_json(*args) end
Returns a JSON
string representing self
:
require 'json/add/complex' puts Complex(2).to_json puts Complex(2.0, 4).to_json
Output:
{"json_class":"Complex","r":2,"i":0} {"json_class":"Complex","r":2.0,"i":4}Source
static VALUE nucomp_to_r(VALUE self) { get_dat1(self); if (RB_FLOAT_TYPE_P(dat->imag) && FLOAT_ZERO_P(dat->imag)) { /* Do nothing here */ } else if (!k_exact_zero_p(dat->imag)) { VALUE imag = rb_check_convert_type_with_id(dat->imag, T_RATIONAL, "Rational", idTo_r); if (NIL_P(imag) || !k_exact_zero_p(imag)) { rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Rational", self); } } return f_to_r(dat->real); }
Returns the value of self.real
as a Rational
, if possible:
Complex.rect(1, 0).to_r Complex.rect(1, Rational(0, 1)).to_r Complex.rect(1, 0.0).to_r
Raises RangeError
if self.imag
is not exactly zero (either Integer(0)
or Rational(0, n)
) and self.imag.to_r
is not exactly zero.
Related: Complex#rationalize
.
static VALUE nucomp_to_s(VALUE self) { return f_format(self, rb_usascii_str_new2(""), rb_String); }
Returns a string representation of self
:
Complex.rect(2).to_s Complex.rect(-8, 6).to_s Complex.rect(0, Rational(1, 2)).to_s Complex.rect(0, Float::INFINITY).to_s Complex.rect(Float::NAN, Float::NAN).to_s
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