# Polynomials

Curve fitting, roots, partial fraction expansions

Polynomials are equations of a single variable with nonnegative integer exponents. MATLAB® represents polynomials with numeric vectors containing the polynomial coefficients ordered by descending power. For example, `[1 -4 4]` corresponds to x2 - 4x + 4. For more information, see Create and Evaluate Polynomials.

## Functions

 `poly` Polynomial with specified roots or characteristic polynomial `polyeig` Polynomial eigenvalue problem `polyfit` Polynomial curve fitting `residue` Partial fraction expansion (partial fraction decomposition) `roots` Polynomial roots `polyval` Polynomial evaluation `polyvalm` Matrix polynomial evaluation `conv` Convolution and polynomial multiplication `deconv` Deconvolution and polynomial division `polyint` Polynomial integration `polyder` Polynomial differentiation

## Topics

• Create and Evaluate Polynomials

This example shows how to represent a polynomial as a vector in MATLAB® and evaluate the polynomial at points of interest.

• Roots of Polynomials

Calculate polynomial roots numerically, graphically, or symbolically.

• Integrate and Differentiate Polynomials

This example shows how to use the `polyint` and `polyder` functions to analytically integrate or differentiate any polynomial represented by a vector of coefficients.

• Polynomial Curve Fitting

This example shows how to fit a polynomial curve to a set of data points using the `polyfit` function.

• Programmatic Fitting

There are many functions in MATLAB that are useful for data fitting.