How to add row values in matrix using a loop?
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I have matrix A
A = [ 1 1 2 0.1;
2 2 3 0.02;
3 3 4 0.05;
4 4 5 0.3;
5 2 6 0.5;
6 2 7 0.4;
7 7 8 0.2;
8 3 9 0.9;
9 4 10 1.3
];
I want to add row values like that using a loop..
X1 = A(1,4)
X2 = A(1,4)+A(2,4)
X3 = A(1,4)+A(2,4)+A(3,4)
X4 = A(1,4)+A(2,4)+A(3,4)+A(4,4)
X5 = A(1,4)+A(2,4)+A(5,4)
X6 = A(1,4)+A(2,4)+A(6,4)
X7 = A(1,4)+A(2,4)+A(6,4)+A(7,4)
X8 = A(1,4)+A(2,4)+A(3,4)+A(8,4)
X9 = A(1,4)+A(2,4)+A(3,4)+A(4,4)+A(4,9)
B= [ X1;
X2;
X3;
X4;
X5;
X6;
X7;
X8;
X9;
];
How can I do that? Any tips?
Many Thanks in advance
5 个评论
Image Analyst
2017-1-3
There doesn't seem to be any rule for which elements of A you pick in getting the B's. It seems to follow a rule like you could say B = cumsum(A(:,4)) through X4 but then everything breaks down after X5 with indexes seeming to be chosen at random. What is the rule? Or are there just tons of typos in your indexes?
Yuli Hartini
2017-1-3
编辑：Yuli Hartini
2017-1-3
Walter Roberson
2017-1-3
According to that rule,
X7 = A(1,4)+A(2,4)+A(6,4)+A(7,4)
should be
X7 = A(1,4)+A(2,4)+A(3,4)+A(4,4)+A(5,4)+A(6,4)+A(7,4)
since you have 7 7 8 0.2 for that row.
I can see how you might be defining the other rows, but not that one.
Yuli Hartini
2017-1-3
Walter Roberson
2017-1-3
None of your examples have A(:,2)=(A(:,3)+1) . In some cases A(:,2)=(A(:,3)-1) .
Your proposed rule is not clear on what to do when the relationship between those two columns does not hold.
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