interpax_fft.idct_mmt

interpax_fft.idct_mmt(x, a, axis=-1, vander=None)Source

Evaluate Chebyshev coefficients a at x ∈ [-1, 1].

Uses matrix multiplication transform, which was benchmarked to be significantly faster than Clenshaw recursion.

Parameters:

  • x (jnp.ndarray) – Real query points where interpolation is desired. Shape of x must broadcast with shape np.delete(a.shape,axis).

  • a (jnp.ndarray) – Discrete Chebyshev transform coefficients.

  • axis (int) – Axis along which to transform.

  • vander (jnp.ndarray) – Precomputed transform matrix. If given returns (vander*a).sum(-1).

Returns:

fq (jnp.ndarray) – Real function value at query points.