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6.46.2 Operations on sparse matrices

All matrix operations can be done on tables that are used to define sparse matrices.


Example.
Create some sparse matrices.
Input:

purge(A):;
A[0..2,0..2]:= [1,2,3]

Output:

KeyValue
⎛
⎝
0,0⎞
⎠
1
⎛
⎝
1,1⎞
⎠
2
⎛
⎝
2,2⎞
⎠
3

Input:

purge(B):;
B[0..1,1..2]:= [1,2]:;
B[0..2,0]:=5

Output:

KeyValue
⎛
⎝
0,0⎞
⎠
5
⎛
⎝
0,1⎞
⎠
1
⎛
⎝
1,0⎞
⎠
5
⎛
⎝
1,2⎞
⎠
2
⎛
⎝
2,0⎞
⎠
5

The usual operations will work on A and B.
Input:

A + B

Output:

KeyValue
⎛
⎝
0,0⎞
⎠
6
⎛
⎝
0,1⎞
⎠
1
⎛
⎝
1,0⎞
⎠
5
⎛
⎝
1,1⎞
⎠
2
⎛
⎝
1,2⎞
⎠
2
⎛
⎝
2,0⎞
⎠
5
⎛
⎝
2,2⎞
⎠
3

Input:

A * B

Output:

KeyValue
⎛
⎝
0,0⎞
⎠
5
⎛
⎝
0,1⎞
⎠
1
⎛
⎝
1,0⎞
⎠
10
⎛
⎝
1,2⎞
⎠
4
⎛
⎝
2,0⎞
⎠
15

Input:

2*A

Output:

KeyValue
⎛
⎝
0,0⎞
⎠
2
⎛
⎝
1,1⎞
⎠
4
⎛
⎝
2,2⎞
⎠
6

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