.. py:module:: ethereum.utils.numeric

Utility Functions For Numeric Operations
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. contents:: Table of Contents
    :backlinks: none
    :local:

Introduction
------------

Numeric operations specific utility functions used in this specification.


.. only:: stage1

Module Contents
---------------


Functions
~~~~~~~~~

.. autoapisummary::
   :nosignatures:

   ethereum.utils.numeric.get_sign
   ethereum.utils.numeric.ceil32
   ethereum.utils.numeric.is_prime
   ethereum.utils.numeric.le_bytes_to_uint32_sequence
   ethereum.utils.numeric.le_uint32_sequence_to_bytes
   ethereum.utils.numeric.le_uint32_sequence_to_uint



Module Details
---------------

get_sign
~~~~~~~~


.. function:: get_sign(value: int) -> int
   :noindexentry:

   Determines the sign of a number.

   :param value: The value whose sign is to be determined.

   :returns: **sign** -- The sign of the number (-1 or 0 or 1).
             The return value is based on math signum function.
   :rtype: `int`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: get_sign

ceil32
~~~~~~


.. function:: ceil32(value: ethereum.base_types.Uint) -> ethereum.base_types.Uint
   :noindexentry:

   Converts a unsigned integer to the next closest multiple of 32.

   :param value: The value whose ceil32 is to be calculated.

   :returns: **ceil32** -- The same value if it's a perfect multiple of 32
             else it returns the smallest multiple of 32
             that is greater than `value`.
   :rtype: `ethereum.base_types.U256`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: ceil32

is_prime
~~~~~~~~


.. function:: is_prime(number: int) -> bool
   :noindexentry:

   Checks if `number` is a prime number.

   :param number: The number to check for primality.

   :returns: **is_number_prime** -- Boolean indicating if `number` is prime or not.
   :rtype: `bool`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: is_prime

le_bytes_to_uint32_sequence
~~~~~~~~~~~~~~~~~~~~~~~~~~~


.. function:: le_bytes_to_uint32_sequence(data: bytes) -> Tuple[ethereum.base_types.Uint32, Ellipsis]
   :noindexentry:

   Convert little endian byte stream `data` to a little endian Uint32
   sequence i.e., the first Uint32 number of the sequence is the least
   significant Uint32 number.

   :param data: The byte stream (little endian) which is to be converted to a Uint32
                stream.

   :returns: **uint32_sequence** -- Sequence of Uint32 numbers obtained from the little endian byte
             stream.
   :rtype: `Tuple[Uint32, ...]`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: le_bytes_to_uint32_sequence

le_uint32_sequence_to_bytes
~~~~~~~~~~~~~~~~~~~~~~~~~~~


.. function:: le_uint32_sequence_to_bytes(sequence: Sequence[ethereum.base_types.Uint32]) -> bytes
   :noindexentry:

   Obtain little endian byte stream from a little endian Uint32 sequence
   i.e., the first Uint32 number of the sequence is the least significant
   Uint32 number.

   Note - In this conversion, the most significant byte (byte at the end of
   the little endian stream) may have leading zeroes. This function doesn't
   take care of removing these leading zeroes as shown in below example.

   >>> le_uint32_sequence_to_bytes([Uint32(8)])
   b'\x08\x00\x00\x00'


   :param sequence: The Uint32 stream (little endian) which is to be converted to a
                    little endian byte stream.

   :returns: **result** -- The byte stream obtained from the little endian Uint32 stream.
   :rtype: `bytes`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: le_uint32_sequence_to_bytes

le_uint32_sequence_to_uint
~~~~~~~~~~~~~~~~~~~~~~~~~~


.. function:: le_uint32_sequence_to_uint(sequence: Sequence[ethereum.base_types.Uint32]) -> ethereum.base_types.Uint
   :noindexentry:

   Obtain Uint from a Uint32 sequence assuming that this sequence is little
   endian i.e., the first Uint32 number of the sequence is the least
   significant Uint32 number.

   :param sequence: The Uint32 stream (little endian) which is to be converted to a Uint.

   :returns: **value** -- The Uint number obtained from the conversion of the little endian
             Uint32 stream.
   :rtype: `Uint`




.. undocinclude:: /../src/ethereum/utils/numeric.py
   :language: python
   :pyobject: le_uint32_sequence_to_uint