Iterates over array elements.
When a block given, passes each successive array element to the block; returns self
:
a = [:foo, 'bar', 2] a.each {|element| puts "#{element.class} #{element}" }
Output:
Symbol foo String bar Integer 2
Allows the array to be modified during iteration:
a = [:foo, 'bar', 2] a.each {|element| puts element; a.clear if element.to_s.start_with?('b') }
Output:
foo bar
When no block given, returns a new Enumerator:
a = [:foo, 'bar', 2] e = a.each e # => #<Enumerator: [:foo, "bar", 2]:each> a1 = e.each {|element| puts "#{element.class} #{element}" }
Output:
Symbol foo String bar Integer 2
Related: each_index
, reverse_each
.
Returns a Hash
containing implementation-dependent counters inside the VM.
This hash includes information about method/constant caches:
{ :constant_cache_invalidations=>2, :constant_cache_misses=>14, :global_cvar_state=>27 }
If USE_DEBUG_COUNTER
is enabled, debug counters will be included.
The contents of the hash are implementation specific and may be changed in the future.
This method is only expected to work on C Ruby.
Returns a 1-character string containing the character represented by the value of self
, according to the given encoding
.
65.chr # => "A" 0.chr # => "\x00" 255.chr # => "\xFF" string = 255.chr(Encoding::UTF_8) string.encoding # => Encoding::UTF_8
Raises an exception if self
is negative.
Related: Integer#ord
.
Returns self
truncated (toward zero) to a precision of ndigits
decimal digits.
When ndigits
is negative, the returned value has at least ndigits.abs
trailing zeros:
555.truncate(-1) # => 550 555.truncate(-2) # => 500 -555.truncate(-2) # => -500
Returns self
when ndigits
is zero or positive.
555.truncate # => 555 555.truncate(50) # => 555
Related: Integer#round
.
Returns the remainder after dividing self
by other
.
Examples:
11.remainder(4) # => 3 11.remainder(-4) # => 3 -11.remainder(4) # => -3 -11.remainder(-4) # => -3 12.remainder(4) # => 0 12.remainder(-4) # => 0 -12.remainder(4) # => 0 -12.remainder(-4) # => 0 13.remainder(4.0) # => 1.0 13.remainder(Rational(4, 1)) # => (1/1)
Returns self
.
Returns 1
.
Returns the value as a rational. The optional argument eps
is always ignored.
Returns the imaginary value for self
:
Complex.rect(7).imag # => 0 Complex.rect(9, -4).imag # => -4
If self
was created with polar coordinates, the returned value is computed, and may be inexact:
Complex.polar(1, Math::PI/4).imag # => 0.7071067811865476 # Square root of 2.
Returns the imaginary value for self
:
Complex.rect(7).imag # => 0 Complex.rect(9, -4).imag # => -4
If self
was created with polar coordinates, the returned value is computed, and may be inexact:
Complex.polar(1, Math::PI/4).imag # => 0.7071067811865476 # Square root of 2.
Returns the absolute value (magnitude) for self
; see polar coordinates:
Complex.polar(-1, 0).abs # => 1.0
If self
was created with rectangular coordinates, the returned value is computed, and may be inexact:
Complex.rectangular(1, 1).abs # => 1.4142135623730951 # The square root of 2.
Returns the conjugate of self
, Complex.rect(self.imag, self.real)
:
Complex.rect(1, 2).conj # => (1-2i)
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)) # => ((2/3)+(3/4)*i) c.numerator # => (8+9i)
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
.
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 # => 6
Note that n.denominator
of a non-rational numeric is 1
.
Related: Complex#numerator
.
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 # => (1/1) Complex.rect(1, Rational(0, 1)).rationalize # => (1/1) Complex.rect(3.14159, 0).rationalize # => (314159/100000)
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) # => (16/5) Complex.rect(3.14159, 0).rationalize(0.01) # => (22/7) Complex.rect(3.14159, 0).rationalize(0.001) # => (201/64) Complex.rect(3.14159, 0).rationalize(0.0001) # => (333/106) Complex.rect(3.14159, 0).rationalize(0.00001) # => (355/113) Complex.rect(3.14159, 0).rationalize(0.000001) # => (7433/2366) Complex.rect(3.14159, 0).rationalize(0.0000001) # => (9208/2931) Complex.rect(3.14159, 0).rationalize(0.00000001) # => (47460/15107) Complex.rect(3.14159, 0).rationalize(0.000000001) # => (76149/24239) Complex.rect(3.14159, 0).rationalize(0.0000000001) # => (314159/100000) Complex.rect(3.14159, 0).rationalize(0.0) # => (3537115888337719/1125899906842624)
Related: Complex#to_r
.
Returns zero as a Rational:
nil.rationalize # => (0/1)
Argument eps
is ignored.
Returns the remainder after dividing self
by other
.
Of the Core and Standard Library classes, only Float
and Rational
use this implementation.
Examples:
11.0.remainder(4) # => 3.0 11.0.remainder(-4) # => 3.0 -11.0.remainder(4) # => -3.0 -11.0.remainder(-4) # => -3.0 12.0.remainder(4) # => 0.0 12.0.remainder(-4) # => 0.0 -12.0.remainder(4) # => -0.0 -12.0.remainder(-4) # => -0.0 13.0.remainder(4.0) # => 1.0 13.0.remainder(Rational(4, 1)) # => 1.0 Rational(13, 1).remainder(4) # => (1/1) Rational(13, 1).remainder(-4) # => (1/1) Rational(-13, 1).remainder(4) # => (-1/1) Rational(-13, 1).remainder(-4) # => (-1/1)
Returns the absolute value of self
.
12.abs #=> 12 (-34.56).abs #=> 34.56 -34.56.abs #=> 34.56
Returns self
truncated (toward zero) to a precision of digits
decimal digits.
Numeric implements this by converting self
to a Float
and invoking Float#truncate
.
Returns true
if self
is less than 0, false
otherwise.
Returns zero.
Returns self
.