.. index:: module, stdlib, math;

.. _stdlib-math:

Math Module ###########

The math module is a standard library module that provides mathematical functions. Import it with:

.. code-block:: vyper

import math

Functions are then called as math.isqrt(x), math.sqrt(d), etc.

.. note::

``import math`` always refers to the standard library module. To import a local file named ``math.vy``, use a relative import: ``from . import math``.

Functions

.. py:function:: sqrt(d: decimal) -> decimal

Return the square root of the provided decimal number, using the Babylonian square root algorithm. The rounding mode is to round down to the nearest epsilon. For instance, ``math.sqrt(0.9999999998) == 0.9999999998``.

.. code-block:: vyper

    import math

    @external
    @view
    def foo(d: decimal) -> decimal:
        return math.sqrt(d)

.. code-block:: vyper

    >>> ExampleContract.foo(9.0)
    3.0

.. py:function:: isqrt(x: uint256) -> uint256

Return the (integer) square root of the provided integer number, using the Babylonian square root algorithm. The rounding mode is to round down to the nearest integer. For instance, ``math.isqrt(101) == 10``.

.. code-block:: vyper

    import math

    @external
    @view
    def foo(x: uint256) -> uint256:
        return math.isqrt(x)

.. code-block:: vyper

    >>> ExampleContract.foo(101)
    10