1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
function C = gb_maxbyrow (op, A)
%GB_MAXBYROW max, by row
% Implements C = max (A, [ ], 2)
% SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2022, All Rights Reserved.
% SPDX-License-Identifier: Apache-2.0
% C = max (A, [ ], 2) reduces each row to a scalar; C is m-by-1
C = gbvreduce (op, A) ;
% if C(i) < 0, but if A(i,:) is sparse, then assign C(i) = 0.
ctype = gbtype (C) ;
if (gb_issigned (ctype))
% d (i) = number of entries in A(i,:); d (i) not present if A(i,:) empty
[m, n] = gbsize (A) ;
d = gbdegree (A, 'row') ;
% d (i) is an explicit zero if A(i,:) has 1 to n-1 entries
d = gbselect (d, '<', int64 (n)) ;
zero = gbnew (0, ctype) ;
if (gbnvals (d) == m)
% all rows A(i,:) have between 1 and n-1 entries
C = gbapply2 (op, C, zero) ;
else
d = gbapply2 (['2nd.' ctype], d, zero) ;
% if d(i) is between 1 and n-1 and C(i) < 0 then C(i) = 0
C = gbeadd (op, C, d) ;
end
end
|
