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    Metadata details:
    filename: test43.m
    path of file: ./repos/SuiteSparse/GraphBLAS/Test/unused
    
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%TEST43 test subref

% SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2023, All Rights Reserved.
% SPDX-License-Identifier: Apache-2.0

fprintf ('\n------------------------------ testing GB_mex_Matrix_subref\n') ;

rng ('default')

    
function test43
%TEST43 test subref

% SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2023, All Rights Reserved.
% SPDX-License-Identifier: Apache-2.0

fprintf ('\n------------------------------ testing GB_mex_Matrix_subref\n') ;

rng ('default')

A = sparse (rand (3,4)) ;
I = uint64 (0:2) ;
J = uint64 (0:3) ;

C0 = A (I+1,J+1) ;
C = GB_mex_Matrix_subref (A, I, J) ;
assert (isequal (C, C0))

C0 = A (:,:) ;
C = GB_mex_Matrix_subref (A, [ ], [ ]) ;
assert (isequal (C, C0))

C0 = A (1,:) ;
C = GB_mex_Matrix_subref (A, uint64(0), [ ]) ;
assert (isequal (C, C0))

C0 = A (:,1) ;
C = GB_mex_Matrix_subref (A, [ ], uint64(0)) ;
assert (isequal (C, C0))

I = uint64 ([0 1]) ;
J = uint64 ([0 1]) ;
A = sparse (rand (4)) ;
C0 = full (A (I+1,J+1)) ;
full (A) ;
C = GB_mex_Matrix_subref (A, I, J) ;
full (C) ;
assert (isequal (C, C0))

I = uint64 ([2 1]) ;
J = uint64 ([3 1]) ;
C0 = full (A (I+1,J+1)) ;
C = GB_mex_Matrix_subref (A, I, J) ;
C = full (C) ;
assert (isequal (C, C0)) ;

fprintf ('-------------------------- problem:\n') ;
% Prob = ssget ('HB/west0067') ; A = Prob.A ;
  Prob = ssget (939) ; A = Prob.A ;
% A = sparse (rand (8000)) ;
A(1,2) =44 ;

fprintf ('-------------------------- case 5, ni large, qsort, no dupl:\n') ;
p = amd (A) ;
fprintf ('builtin:\n') ;
tic
A1 = A (p,p) ;
t0 = toc ;
p0 = uint64 (p-1) ;
fprintf ('GB:\n') ;
tic
A2 = GB_mex_Matrix_subref (A, p0, p0) ;
t1 = toc ;

fprintf ('CSparse permute:\n') ;
try
    tic
    A3 = cs_permute (A, p, p) ;
    t2 = toc ;
    ok = isequal (A1, A3) ;
catch
    % CSparse not available
    t2 = 0 ;
    ok = true ;
end