wavefunction91 / IntegratorXX

Reusable DFT Grids for the Masses
BSD 3-Clause "New" or "Revised" License
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Implement Gauss-Jacobi Quadrature Rule #55

Open wavefunction91 opened 1 year ago

wavefunction91 commented 1 year ago

The Gauss-Jacobi quadrature integrates functions of the form

$$ \int{-1}^1 f(x) (1-x)^\alpha (1+x)^\beta\mathrm{d}x \approx \sum{i=1}^n w_i f(x_i) $$

where ${x_i}$ are the nodes of $n$-th order Jacobi polynomial, $P^{(\alpha,\beta)}_n$. The Chebyshev and Legendre polynomials are special cases of the polynomials which already have quadrature rules generated.