poly_basis_fn    1076 magick/distort.c           terms[j] = poly_basis_fn(j,arguments[i+cp_x],arguments[i+cp_y]);
poly_basis_fn    2503 magick/distort.c               s.x  += poly_basis_fn(k,d.x,d.y)*coeff[2+k];
poly_basis_fn    2506 magick/distort.c               s.y  += poly_basis_fn(k,d.x,d.y)*coeff[2+k+nterms];