Description
f++g -- computes the direct sum of two maps between modules.
If an argument is a ring element or integer, it is promoted to a one by one matrix.
i1 : R = ZZ/101[a..c];
|
i2 : vars R ++ transpose vars R
o2 = {0} | a b c 0 |
{-1} | 0 0 0 a |
{-1} | 0 0 0 b |
{-1} | 0 0 0 c |
4 4
o2 : Matrix R <-- R
|
i3 : oo^[1]
o3 = {-1} | 0 0 0 a |
{-1} | 0 0 0 b |
{-1} | 0 0 0 c |
3 4
o3 : Matrix R <-- R
|
i4 : a++b++c
o4 = | a 0 0 |
| 0 b 0 |
| 0 0 c |
3 3
o4 : Matrix R <-- R
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Selecting rows or columns of blocks: