Functions for working with integers.
Some functions that work on integers are found in Kernel
:
Returns the ordered digits for the given integer
Performs a floored integer division
Returns the greatest common divisor of the two given integers
Determines if an integer
is even
Determines if integer
is odd
Computes the modulo remainder of an integer division
Parses a text representation of an integer
Returns a charlist which corresponds to the text representation of the given integer
Returns a charlist which corresponds to the text representation of integer
in the given base
Returns a binary which corresponds to the text representation of integer
Returns a binary which corresponds to the text representation of integer
in the given base
Returns the integer represented by the ordered digits
digits(integer(), pos_integer()) :: [integer(), ...]
Returns the ordered digits for the given integer
.
An optional base
value may be provided representing the radix for the returned digits. This one must be an integer >= 2.
iex> Integer.digits(123) [1, 2, 3] iex> Integer.digits(170, 2) [1, 0, 1, 0, 1, 0, 1, 0] iex> Integer.digits(-170, 2) [-1, 0, -1, 0, -1, 0, -1, 0]
floor_div(integer(), neg_integer() | pos_integer()) :: integer()
Performs a floored integer division.
Raises an ArithmeticError
exception if one of the arguments is not an integer, or when the divisor
is 0
.
Integer.floor_div/2
performs floored integer division. This means that the result is always rounded towards negative infinity.
If you want to perform truncated integer division (rounding towards zero), use Kernel.div/2
instead.
iex> Integer.floor_div(5, 2) 2 iex> Integer.floor_div(6, -4) -2 iex> Integer.floor_div(-99, 2) -50
gcd(integer(), integer()) :: pos_integer()
gcd(0, 0) :: 0
Returns the greatest common divisor of the two given integers.
The greatest common divisor (GCD) of integer1
and integer2
is the largest positive integer that divides both integer1
and integer2
without leaving a remainder.
By convention, gcd(0, 0)
returns 0
.
iex> Integer.gcd(2, 3) 1 iex> Integer.gcd(8, 12) 4 iex> Integer.gcd(8, -12) 4 iex> Integer.gcd(10, 0) 10 iex> Integer.gcd(7, 7) 7 iex> Integer.gcd(0, 0) 0
Determines if an integer
is even.
Returns true
if the given integer
is an even number, otherwise it returns false
.
Allowed in guard clauses.
iex> Integer.is_even(10) true iex> Integer.is_even(5) false iex> Integer.is_even(-10) true iex> Integer.is_even(0) true
Determines if integer
is odd.
Returns true
if the given integer
is an odd number, otherwise it returns false
.
Allowed in guard clauses.
iex> Integer.is_odd(5) true iex> Integer.is_odd(6) false iex> Integer.is_odd(-5) true iex> Integer.is_odd(0) false
mod(integer(), neg_integer() | pos_integer()) :: integer()
Computes the modulo remainder of an integer division.
Integer.mod/2
uses floored division, which means that the result will always have the sign of the divisor
.
Raises an ArithmeticError
exception if one of the arguments is not an integer, or when the divisor
is 0
.
iex> Integer.mod(5, 2) 1 iex> Integer.mod(6, -4) -2
parse(binary(), 2..36) :: {integer(), binary()} | :error
Parses a text representation of an integer.
An optional base
to the corresponding integer can be provided. If base
is not given, 10 will be used.
If successful, returns a tuple in the form of {integer, remainder_of_binary}
. Otherwise :error
.
Raises an error if base
is less than 2 or more than 36.
If you want to convert a string-formatted integer directly to an integer, String.to_integer/1
or String.to_integer/2
can be used instead.
iex> Integer.parse("34") {34, ""} iex> Integer.parse("34.5") {34, ".5"} iex> Integer.parse("three") :error iex> Integer.parse("34", 10) {34, ""} iex> Integer.parse("f4", 16) {244, ""} iex> Integer.parse("Awww++", 36) {509216, "++"} iex> Integer.parse("fab", 10) :error iex> Integer.parse("a2", 38) ** (ArgumentError) invalid base 38
to_charlist(integer()) :: charlist()
Returns a charlist which corresponds to the text representation of the given integer
.
Inlined by the compiler.
iex> Integer.to_charlist(123) '123' iex> Integer.to_charlist(+456) '456' iex> Integer.to_charlist(-789) '-789' iex> Integer.to_charlist(0123) '123'
to_charlist(integer(), 2..36) :: charlist()
Returns a charlist which corresponds to the text representation of integer
in the given base
.
base
can be an integer between 2 and 36.
Inlined by the compiler.
iex> Integer.to_charlist(100, 16) '64' iex> Integer.to_charlist(-100, 16) '-64' iex> Integer.to_charlist(882_681_651, 36) 'ELIXIR'
to_string(integer()) :: String.t()
Returns a binary which corresponds to the text representation of integer
.
Inlined by the compiler.
iex> Integer.to_string(123) "123" iex> Integer.to_string(+456) "456" iex> Integer.to_string(-789) "-789" iex> Integer.to_string(0123) "123"
to_string(integer(), 2..36) :: String.t()
Returns a binary which corresponds to the text representation of integer
in the given base
.
base
can be an integer between 2 and 36.
Inlined by the compiler.
iex> Integer.to_string(100, 16) "64" iex> Integer.to_string(-100, 16) "-64" iex> Integer.to_string(882_681_651, 36) "ELIXIR"
undigits([integer()], pos_integer()) :: integer()
Returns the integer represented by the ordered digits
.
An optional base
value may be provided representing the radix for the digits
. Base has to be an integer greater or equal than 2
.
iex> Integer.undigits([1, 2, 3]) 123 iex> Integer.undigits([1, 4], 16) 20 iex> Integer.undigits([]) 0
© 2012 Plataformatec
Licensed under the Apache License, Version 2.0.
https://hexdocs.pm/elixir/1.7.3/Integer.html