Library
Module
Module type
Parameter
Class
Class type
include Ff_sig.BASE
exception Not_in_field of Bytes.t
val order : Z.t
The order of the finite field
val check_bytes : Bytes.t -> bool
check_bytes bs
returns true
if bs
is a correct byte representation of a field element
val zero : t
The neutral element for the addition
val one : t
The neutral element for the multiplication
val is_zero : t -> bool
is_zero x
returns true
if x
is the neutral element for the addition
val is_one : t -> bool
is_one x
returns true
if x
is the neutral element for the multiplication
val random : ?state:Random.State.t -> unit -> t
Use carefully! random ()
returns a random element of the field. A state for the PRNG can be given to initialize the PRNG in the requested state. If no state is given, no initialisation is performed
val non_null_random : ?state:Random.State.t -> unit -> t
Use carefully! non_null_random ()
returns a non null random element of the field. A state for the PRNG can be given to initialize the PRNG in the requested state. If no state is given, no initialisation is performed
negate x
returns -x mod order
. Equivalently, negate x
returns the unique y
such that x + y mod order = 0
Construct a value of type t
from the bytes representation in little endian of the field element. For non prime fields, the encoding starts with the coefficient of the constant monomial. Raise Not_in_field
if the bytes do not represent an element in the field.
From a predefined little endian bytes representation, construct a value of type t
. The same representation than of_bytes_exn
is used. Return None
if the bytes do not represent an element in the field.
Convert the value t to a bytes representation. The number of bytes is size_in_bytes
and the encoding must be in little endian. For instance, the encoding of 1
in prime fields is always a bytes sequence of size size_in_bytes
starting with the byte 0b00000001
. For non prime fields, the encoding starts with the coefficient of the constant monomial.
val factor_power_of_two : int * Z.t
Returns s, q
such that order - 1 = 2^s * q
val of_string : string -> t
Create a value t from a predefined string representation. It is not required that to_string of_string t = t. By default, decimal representation of the number is used, modulo the order of the field
val to_string : t -> string
String representation of a value t. It is not required that to_string of_string t = t. By default, decimal representation of the number is used
of_z x
builds an element t from the Zarith element x
. mod order
is applied if x >= order
to_z x
builds a Zarith element, using the decimal representation. Arithmetic on the result can be done using the modular functions on integers
Returns the Legendre symbol of the parameter. Note it does not work for p = 2
val is_quadratic_residue : t -> bool
is_quadratic_residue x
returns true
if x
is a quadratic residue i.e. if there exists n
such that n^2 mod p = 1