jax.numpy.polyder

jax.numpy.polyder(p, m=1)

Returns the coefficients of the derivative of specified order of a polynomial.

JAX implementation of numpy.polyder().

Parameters:

• p (ArrayLike) – Array of polynomials coefficients.

• m (int) – Order of differentiation (positive integer). Default is 1. It must be specified statically.

Returns:

An array of polynomial coefficients representing the derivative.

Return type:

Array

Note

jax.numpy.polyder() differs from numpy.polyder() when an integer array is given. NumPy returns the result with dtype int whereas JAX returns the result with dtype float.

See also

• jax.numpy.polyint(): Computes the integral of polynomial.

• jax.numpy.polyval(): Evaluates a polynomial at specific values.

Examples

The first order derivative of the polynomial \(2 x^3 - 5 x^2 + 3 x - 1\) is \(6 x^2 - 10 x +3\):

>>> p = jnp.array([2, -5, 3, -1])
>>> jnp.polyder(p)
Array([  6., -10.,   3.], dtype=float32)

and its second order derivative is \(12 x - 10\):

>>> jnp.polyder(p, m=2)
Array([ 12., -10.], dtype=float32)