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numpy.polynomial.polyutils.mapparms

numpy.poly1d

# Poly1d¶

## Basics¶

 `poly1d`(c_or_r[, r, variable]) A one-dimensional polynomial class. `polyval`(p, x) Evaluate a polynomial at specific values. `poly`(seq_of_zeros) Find the coefficients of a polynomial with the given sequence of roots. Return the roots of a polynomial with coefficients given in p.

## Fitting¶

 `polyfit`(x, y, deg[, rcond, full, w, cov]) Least squares polynomial fit.

## Calculus¶

 `polyder`(p[, m]) Return the derivative of the specified order of a polynomial. `polyint`(p[, m, k]) Return an antiderivative (indefinite integral) of a polynomial.

## Arithmetic¶

 `polyadd`(a1, a2) Find the sum of two polynomials. `polydiv`(u, v) Returns the quotient and remainder of polynomial division. `polymul`(a1, a2) Find the product of two polynomials. `polysub`(a1, a2) Difference (subtraction) of two polynomials.

## Warnings¶

 `RankWarning` Issued by `polyfit` when the Vandermonde matrix is rank deficient.