1 //------------------------------------------------------------------------------
2 // GB_positional_offset: return the offset of a positional operator
3 //------------------------------------------------------------------------------
4
5 // SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2021, All Rights Reserved.
6 // SPDX-License-Identifier: Apache-2.0
7
8 //------------------------------------------------------------------------------
9
10 #include "GB.h"
11
GB_positional_offset(GB_Opcode opcode)12 int64_t GB_positional_offset // return 0 or 1
13 (
14 GB_Opcode opcode // opcode of positional operator
15 )
16 {
17
18 switch (opcode)
19 {
20
21 // these operators are offset by one
22 case GB_POSITIONI1_opcode : // z = position_i1(A(i,j)) == i+1
23 case GB_FIRSTI1_opcode : // z = first_i1(A(i,j),y) == i+1
24 case GB_SECONDI1_opcode : // z = second_i1(x,A(i,j)) == i+1
25 case GB_POSITIONJ1_opcode : // z = position_j1(A(i,j)) == j+1
26 case GB_FIRSTJ1_opcode : // z = first_j1(A(i,j),y) == j+1
27 case GB_SECONDJ1_opcode : // z = second_j1(x,A(i,j)) == j+1
28 return (1) ;
29
30 // all other operators have no offset
31 default:
32 return (0) ;
33 }
34 }
35
36