[GAP Forum] An elementary question about matrices

[Laurent Bartholdi]

Dear Josef,
There is one:
gap> A := List([1..10],i->List([1..10],j->10*i+j));
[ [ 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ], [ 21, 22, 23, 24, 25,
26, 27, 28, 29, 30 ], [ 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 ],
  [ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 ], [ 51, 52, 53, 54, 55,
56, 57, 58, 59, 60 ], [ 61, 62, 63, 64, 65, 66, 67, 68, 69, 70 ],
  [ 71, 72, 73, 74, 75, 76, 77, 78, 79, 80 ], [ 81, 82, 83, 84, 85,
86, 87, 88, 89, 90 ], [ 91, 92, 93, 94, 95, 96, 97, 98, 99, 100 ],
  [ 101, 102, 103, 104, 105, 106, 107, 108, 109, 110 ] ]
gap> S := [2,4,6];
[ 2, 4, 6 ]
gap> T := [3,5,7];
[ 3, 5, 7 ]
gap> A{S}{T};
[ [ 23, 25, 27 ], [ 43, 45, 47 ], [ 63, 65, 67 ] ]

-- 
Laurent Bartholdi          \  laurent.bartholdi<at>gmail<dot>com
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