pytc.xtc._get_tucker_x_factors¶

pytc.xtc._get_tucker_x_factors(kernels)[source]¶

Return a validated (U, Z) Tucker-X representation, if present.

A factorized X deliberately uses a different key from the dense X dataset. That prevents an approximate calculation from accidentally falling back to, or preloading, the full tensor. The representation is X[r,s,c] ~= U[r,a] Z[a,b,c] U[s,b].