1function C = GB_spec_Col_assign (C, Mask, accum, A, I, j, descriptor) 2%GB_SPEC_COL_ASSIGN a MATLAB mimic of GrB_Col_assign 3% 4% Usage: 5% C = GB_spec_Col_assign (C, Mask, accum, A, I, j, descriptor) 6% 7% Computes C<Mask>(I,j) = accum(C(I,j),A), in GraphBLAS notation. 8% 9% This function does the same thing as GrB_Col_assign 10 11% SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2021, All Rights Reserved. 12% SPDX-License-Identifier: Apache-2.0 13 14%------------------------------------------------------------------------------- 15% get inputs 16%------------------------------------------------------------------------------- 17 18if (nargout > 1 || nargin ~= 7) 19 error ('usage: C = GB_spec_Col_assign (C, Mask, accum, A, I, j, descriptor)') ; 20end 21 22if (length (j) ~= 1) 23 error ('j must be a scalar') ; 24end 25 26% Convert inputs to dense matrices with explicit patterns and types, 27C = GB_spec_matrix (C) ; 28 29% extract the C(:,j) column 30X.matrix = C.matrix (:,j) ; 31X.pattern = C.pattern (:,j) ; 32X.class = C.class ; 33 34% X<Mask>(I) = accum (X(I),A) 35X = GB_spec_assign (X, Mask, accum, A, I, 1, descriptor, 0) ; 36 37% put the C(:,j) colum back 38C.matrix (:,j) = X.matrix ; 39C.pattern (:,j) = X.pattern ; 40 41