How do I sum a vector (row) to a matrix?

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If I have
A=[1 0 0 1;
-1 0 1 1;
1 1 1 1]
B=[1 2 2 1]
How do I add the vector B to the 1st row of A so I get:
A=[2 2 2 3;
-1 0 1 1;
1 1 1 1]

Accepted Answer

Star Strider
Star Strider on 16 Nov 2021
This involves a bit of indexing.
Note that the rest of ‘A’ is unchnaged, and onlly ‘A(1,:)’ is involved in the operation.
A=[1 0 0 1;
-1 0 1 1;
1 1 1 1];
B=[1 2 2 1];
A(1,:) = A(1,:) + B
A = 3×4
2 2 2 2 -1 0 1 1 1 1 1 1
.

More Answers (1)

the cyclist
the cyclist on 16 Nov 2021
Edited: the cyclist on 16 Nov 2021
A=[1 0 0 1;
-1 0 1 1;
1 1 1 1];
B=[1 2 2 1];
A(1,:) = A(1,: ) + B
A = 3×4
2 2 2 2 -1 0 1 1 1 1 1 1

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