# Numeric and Mathematical Modules

The modules described in this chapter provide numeric and math-related functions and data types. The `numbers` module defines an abstract hierarchy of numeric types. The `math` and `cmath` modules contain various mathematical functions for floating-point and complex numbers. The `decimal` module supports exact representations of decimal numbers, using arbitrary precision arithmetic.

The following modules are documented in this chapter:

- `numbers` — Numeric abstract base classes
  - The numeric tower
  - Notes for type implementors
    - Adding More Numeric ABCs
    - Implementing the arithmetic operations
- `math` — Mathematical functions
  - Number-theoretic and representation functions
  - Power and logarithmic functions
  - Trigonometric functions
  - Angular conversion
  - Hyperbolic functions
  - Special functions
  - Constants
- `cmath` — Mathematical functions for complex numbers
  - Conversions to and from polar coordinates
  - Power and logarithmic functions
  - Trigonometric functions
  - Hyperbolic functions
  - Classification functions
  - Constants
- `decimal` — Decimal fixed point and floating point arithmetic
  - Quick-start Tutorial
  - Decimal objects
    - Logical operands
  - Context objects
  - Constants
  - Rounding modes
  - Signals
  - Floating Point Notes
    - Mitigating round-off error with increased precision
    - Special values
  - Working with threads
  - Recipes
  - Decimal FAQ
- `fractions` — Rational numbers
- `random` — Generate pseudo-random numbers
  - Bookkeeping functions
  - Functions for bytes
  - Functions for integers
  - Functions for sequences
  - Discrete distributions
  - Real-valued distributions
  - Alternative Generator
  - Notes on Reproducibility
  - Examples
  - Recipes
- `statistics` — Mathematical statistics functions
  - Averages and measures of central location
  - Measures of spread
  - Statistics for relations between two inputs
  - Function details
  - Exceptions
  - `NormalDist` objects
    - `NormalDist` Examples and Recipes
      - Classic probability problems
      - Monte Carlo inputs for simulations
      - Approximating binomial distributions
      - Naive bayesian classifier
      - Kernel density estimation