pytc.legacy.kmat.calc_K3_isdf

pytc.legacy.kmat.calc_K3_isdf(C_rho, xi_rho, jastrow_factor, grid_points, weights, batch_size=None)

Directly evaluate <pq|(∇₁u(r₁,r₂))²|rs> using ISDF intermediates with batched processing.

Parameters:

• C_rho – (Nb^2, n_fused) Selected columns for rho

• xi_rho – (n_fused, N_grid) Interpolation coeffs for rho

• jastrow_factor – Jastrow instance for computing gradients

• grid_points – (N_grid, 3) Grid points

• weights – (N_grid,) Grid weights

• batch_size – Optional batch size for r2 coordinate

Returns:

(Nb^2, Nb^2) array in chemists’ notation (pr|qs)