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abstract struct Number
inherits Value

The top-level number type.

Included modules

Comparable Comparable Steppable

Direct known subclasses

BigDecimal BigRational Float Int

Constants

SI_PREFIXES = { {'y', 'z', 'a', 'f', 'p', 'n', 'µ', 'm'}, {nil, 'k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'} }

Default SI prefixes ordered by magnitude.

SI_PREFIXES_PADDED = ->(magnitude : Int32, _number : Float64) domagnitude = Number.prefix_index(magnitude){magnitude, ( magnitude == 0 ? " " : si_prefix(magnitude))}end

SI prefixes used by #humanize. Equal to SI_PREFIXES but prepends the prefix with a space character.

Class methods

.si_prefix(magnitude : Int, prefixes = SI_PREFIXES) : Char?

Returns the SI prefix for magnitude.

Number.si_prefix(3) # => 'k'
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.additive_identity : self

Returns the additive identity of this type.

For numerical types, it is the value 0 expressed in the respective type.

Int32.additive_identity   # => 0
Float64.additive_identity # => 0.0
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.multiplicative_identity : self

Returns the multiplicative identity of this type.

For numerical types, it is the value 1 expressed in the respective type.

Int32.multiplicative_identity   # => 1
Float64.multiplicative_identity # => 1.0
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.zero : self

Returns the value zero in the respective type.

Int32.zero   # => 0
Float64.zero # => 0.0
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Methods

#*(other : Complex)

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#*(other : BigFloat)

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#+(other : BigFloat)

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#+(other : Complex)

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#+

Returns self.

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#-(other : Complex)

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#-(other : BigFloat)

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#/(other : Complex)

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#/(other : BigFloat)

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#//(other)

Divides self by other using floored division.

The result will be of the same type as self.

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#<=>(other : BigFloat)

The comparison operator. Returns 0 if the two objects are equal, a negative number if this object is considered less than other, a positive number if this object is considered greater than other, or nil if the two objects are not comparable.

Subclasses define this method to provide class-specific ordering.

The comparison operator is usually used to sort values:

# Sort in a descending way:
[3, 1, 2].sort { |x, y| y <=> x } # => [3, 2, 1]

# Sort in an ascending way:
[3, 1, 2].sort { |x, y| x <=> y } # => [1, 2, 3]
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#<=>(other) : Int32?

The comparison operator.

Returns: - -1 if self is less than other - 0 if self is equal to other - -1 if self is greater than other - nil if self is NaN or other is NaN, because NaN values are not comparable

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#==(other : Complex)

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#abs

Returns the absolute value of this number.

123.abs  # => 123
-123.abs # => 123
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#abs2

Returns the square of self (self * self).

4.abs2   # => 16
1.5.abs2 # => 2.25
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#cis

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#divmod(number)

Returns a Tuple of two elements containing the quotient and modulus obtained by dividing self by number.

11.divmod(3)  # => {3, 2}
11.divmod(-3) # => {-4, -1}
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#format(separator = '.', delimiter = ',', decimal_places : Int? = nil, *, group : Int = 3, only_significant : Bool = false) : String

Prints this number as a String using a customizable format.

separator is used as decimal separator, delimiter as thousands delimiter between batches of group digits.

If decimal_places is nil, all significant decimal places are printed (similar to #to_s). If the argument has a numeric value, the number of visible decimal places will be fixed to that amount.

Trailing zeros are omitted if only_significant is true.

123_456.789.format                                            # => "123,456.789"
123_456.789.format(',', '.')                                  # => "123.456,789"
123_456.789.format(decimal_places: 2)                         # => "123,456.79"
123_456.789.format(decimal_places: 6)                         # => "123,456.789000"
123_456.789.format(decimal_places: 6, only_significant: true) # => "123,456.789"
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#format(io : IO, separator = '.', delimiter = ',', decimal_places : Int? = nil, *, group : Int = 3, only_significant : Bool = false) : Nil

Prints this number as a String using a customizable format.

separator is used as decimal separator, delimiter as thousands delimiter between batches of group digits.

If decimal_places is nil, all significant decimal places are printed (similar to #to_s). If the argument has a numeric value, the number of visible decimal places will be fixed to that amount.

Trailing zeros are omitted if only_significant is true.

123_456.789.format                                            # => "123,456.789"
123_456.789.format(',', '.')                                  # => "123.456,789"
123_456.789.format(decimal_places: 2)                         # => "123,456.79"
123_456.789.format(decimal_places: 6)                         # => "123,456.789000"
123_456.789.format(decimal_places: 6, only_significant: true) # => "123,456.789"
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#humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Indexable = SI_PREFIXES) : Nil

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

See Int#humanize_bytes to format a file size.

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#humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Proc) : Nil

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

This methods yields the order of magnitude and self and expects the block to return a Tuple(Int32, _) containing the (adjusted) magnitude and unit. The magnitude is typically adjusted to a multiple of 3.

def humanize_length(number)
  number.humanize do |magnitude, number|
    case magnitude
    when -2, -1 then {-2, " cm"}
    when .>=(4)
      {3, " km"}
    else
      magnitude = Number.prefix_index(magnitude)
      {magnitude, " #{Number.si_prefix(magnitude)}m"}
    end
  end
end

humanize_length(1_420) # => "1.42 km"
humanize_length(0.23)  # => "23.0 cm"

See Int#humanize_bytes to format a file size.

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#humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes = SI_PREFIXES) : String

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

See Int#humanize_bytes to format a file size.

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#humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, &prefixes : Int32, Float64 -> Tuple(Int32, _) | Tuple(Int32, _, Bool)) : Nil

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

This methods yields the order of magnitude and self and expects the block to return a Tuple(Int32, _) containing the (adjusted) magnitude and unit. The magnitude is typically adjusted to a multiple of 3.

def humanize_length(number)
  number.humanize do |magnitude, number|
    case magnitude
    when -2, -1 then {-2, " cm"}
    when .>=(4)
      {3, " km"}
    else
      magnitude = Number.prefix_index(magnitude)
      {magnitude, " #{Number.si_prefix(magnitude)}m"}
    end
  end
end

humanize_length(1_420) # => "1.42 km"
humanize_length(0.23)  # => "23.0 cm"

See Int#humanize_bytes to format a file size.

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#humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, &) : String

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

This methods yields the order of magnitude and self and expects the block to return a Tuple(Int32, _) containing the (adjusted) magnitude and unit. The magnitude is typically adjusted to a multiple of 3.

def humanize_length(number)
  number.humanize do |magnitude, number|
    case magnitude
    when -2, -1 then {-2, " cm"}
    when .>=(4)
      {3, " km"}
    else
      magnitude = Number.prefix_index(magnitude)
      {magnitude, " #{Number.si_prefix(magnitude)}m"}
    end
  end
end

humanize_length(1_420) # => "1.42 km"
humanize_length(0.23)  # => "23.0 cm"

See Int#humanize_bytes to format a file size.

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#humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Proc) : String

Pretty prints this number as a String in a human-readable format.

This is particularly useful if a number can have a wide value range and the exact value is less relevant.

It rounds the number to the nearest thousands magnitude with precision number of significant digits. The order of magnitude is expressed with an appended quantifier. By default, SI prefixes are used (see SI_PREFIXES).

1_200_000_000.humanize # => "1.2G"
0.000_000_012.humanize # => "12.0n"

If significant is false, the number of precision digits is preserved after the decimal separator.

1_234.567_890.humanize(precision: 2)                     # => "1.2k"
1_234.567_890.humanize(precision: 2, significant: false) # => "1.23k"

separator describes the decimal separator, delimiter the thousands delimiter (see #format).

This methods yields the order of magnitude and self and expects the block to return a Tuple(Int32, _) containing the (adjusted) magnitude and unit. The magnitude is typically adjusted to a multiple of 3.

def humanize_length(number)
  number.humanize do |magnitude, number|
    case magnitude
    when -2, -1 then {-2, " cm"}
    when .>=(4)
      {3, " km"}
    else
      magnitude = Number.prefix_index(magnitude)
      {magnitude, " #{Number.si_prefix(magnitude)}m"}
    end
  end
end

humanize_length(1_420) # => "1.42 km"
humanize_length(0.23)  # => "23.0 cm"

See Int#humanize_bytes to format a file size.

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#i

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#negative? : Bool

Returns true if self is less than zero.

-1.negative? # => true
0.negative?  # => false
1.negative?  # => false
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#positive? : Bool

Returns true if self is greater than zero.

-1.positive? # => false
0.positive?  # => false
1.positive?  # => true
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#round(digits : Number, base = 10, *, mode : RoundingMode = :ties_even)

Rounds this number to a given precision.

Rounds to the specified number of digits after the decimal place, (or before if negative), in base base.

The rounding mode controls the direction of the rounding. The default is RoundingMode::TIES_EVEN which rounds to the nearest integer, with ties (fractional value of 0.5) being rounded to the even neighbor (Banker's rounding).

-1763.116.round(2) # => -1763.12
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#round(mode : RoundingMode = :ties_even) : self

Rounds self to an integer value using rounding mode.

The rounding mode controls the direction of the rounding. The default is RoundingMode::TIES_EVEN which rounds to the nearest integer, with ties (fractional value of 0.5) being rounded to the even neighbor (Banker's rounding).

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#sign

Returns the sign of this number as an Int32. * -1 if this number is negative * 0 if this number is zero * 1 if this number is positive

123.sign # => 1
0.sign   # => 0
-42.sign # => -1
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#significant(digits, base = 10)

Keeps digits significant digits of this number in the given base.

1234.567.significant(1) # => 1000
1234.567.significant(2) # => 1200
1234.567.significant(3) # => 1230
1234.567.significant(4) # => 1235
1234.567.significant(5) # => 1234.6
1234.567.significant(6) # => 1234.57
1234.567.significant(7) # => 1234.567
1234.567.significant(8) # => 1234.567

15.159.significant(1, base = 2) # => 16
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#step(*, to limit = nil, exclusive : Bool = false)

Creates a StaticArray of self with the given values, which will be casted to this type with the new method (defined in each Number type).

floats = Float64.static_array(1, 2, 3, 4)
floats.class # => StaticArray(Float64, 4)

ints = Int64.static_array(1, 2, 3)
ints.class # => StaticArray(Int64, 3)
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#step(*, to limit = nil, exclusive : Bool = false, &) : Nil

Creates a StaticArray of self with the given values, which will be casted to this type with the new method (defined in each Number type).

floats = Float64.static_array(1, 2, 3, 4)
floats.class # => StaticArray(Float64, 4)

ints = Int64.static_array(1, 2, 3)
ints.class # => StaticArray(Int64, 3)
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#to_big_f

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#to_c

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#to_yaml(yaml : YAML::Nodes::Builder)

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#zero? : Bool

Returns true if self is equal to zero.

0.zero? # => true
5.zero? # => false
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Macros

[](*nums)

Creates an Array of self with the given values, which will be casted to this type with the new method (defined in each Number type).

floats = Float64[1, 2, 3, 4]
floats.class # => Array(Float64)

ints = Int64[1, 2, 3]
ints.class # => Array(Int64)
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slice(*nums, read_only = false)

Creates a Slice of self with the given values, which will be casted to this type with the new method (defined in each Number type).

The slice is allocated on the heap.

floats = Float64.slice(1, 2, 3, 4)
floats.class # => Slice(Float64)

ints = Int64.slice(1, 2, 3)
ints.class # => Slice(Int64)
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static_array(*nums)

Creates a StaticArray of self with the given values, which will be casted to this type with the new method (defined in each Number type).

floats = Float64.static_array(1, 2, 3, 4)
floats.class # => StaticArray(Float64, 4)

ints = Int64.static_array(1, 2, 3)
ints.class # => StaticArray(Int64, 3)
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