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14.4.3  Operations on sparse matrices

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

Example

Create some sparse matrices.

purge(A):; A[0..2,0..2]:=[1,2,3]
     
KeyValue
⎛
⎝		0,0⎞
⎠
1
⎛
⎝		1,1⎞
⎠
2
⎛
⎝		2,2⎞
⎠
3
          
purge(B):; B[0..1,1..2]:=[1,2]:; B[0..2,0]:=5
     
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.

A+B
     
KeyValue
⎛
⎝		0,0⎞
⎠
6
⎛
⎝		0,1⎞
⎠
1
⎛
⎝		1,0⎞
⎠
5
⎛
⎝		1,1⎞
⎠
2
⎛
⎝		1,2⎞
⎠
2
⎛
⎝		2,0⎞
⎠
5
⎛
⎝		2,2⎞
⎠
3
          
A*B
     
KeyValue
⎛
⎝		0,0⎞
⎠
5
⎛
⎝		0,1⎞
⎠
1
⎛
⎝		1,0⎞
⎠
10
⎛
⎝		1,2⎞
⎠
4
⎛
⎝		2,0⎞
⎠
15
          
2*A
     
KeyValue
⎛
⎝		0,0⎞
⎠
2
⎛
⎝		1,1⎞
⎠
4
⎛
⎝		2,2⎞
⎠
6
          
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