Add matrix to matrix

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ha ha
ha ha 2017-8-30
编辑： Stephen23 2017-9-1
Let's say: A=zeros(7,2):
A=[ 0 0
0 0
0 0
0 0
0 0
0 0
0 0]
B=[4 1 3] ; C=[1 1 1] ;
D=[2 5 7 6]; E=[2 2 2 2]
How can I add two matrix B,C,D,E to matrix A to get the result as follows:
F=[ 4 1 ......add B, C.......
1 1 ......add B, C.......
3 1 ......add B, C.......
2 2 ......add D, E.......
5 2 ......add D, E......
7 2 ......add D, E......
6 2] ......add D, E......
In general, let's say :
A=zeros(1000,2)
B1=[1; 2; 3;....100] ; index_B1= [1;1;1;.....1] {100 element 1}
B2=[101;102;103....300]; index_B2= [2;2;2;.....2] {200 element 2}
B3=[301;302;303....600]; index_B3= [3;3;3;.....3] {300 element 3}
..................................................................
B7=[801;802;803....850]; index_B7= [7;7;7;.....7] {50 element 7}
...................................................................
Bi=[921;922;923....1000]; index_Bi=[i;i;i;.....i] {80 element i}
1/ How to create matrix index_Bi according to the number of element in matrix Bi? (If possible please use while or for ...loop to do)
2/ After that, How to add two matrices (Bi & index_Bi) to matrix A, we will have the result:
F=[ B1 index_B1
B2 index_B2
B3 index_B3
..............
B7 index_B7
.............
Bi index_Bi]
  1 个评论
Stephen23
Stephen23 2017-8-31
编辑：Stephen23 2017-8-31
"if possible please use while or for ...loop to do" It is possible, but it is not a good way to write code. You should read this to know why, and what the better alternatives are (hint: indexing):
https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

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采纳的回答

Andrei Bobrov
Andrei Bobrov 2017-8-30
编辑：Andrei Bobrov 2017-8-30
B = {B1;B2;B3;B4...;Bi}; % Please create B array.
n = cellfun(@numel,B);
A = [cell2mat(B),repelem((1:numel(n))',n)];
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显示 3更早的评论
Guillaume
Guillaume 2017-8-31
You should never have matrix B1, B2, ... Bn in your workspace. As soon as you start numbering matrices, you should stop and change the way you work. These numbered matrices are obviously relatedm they should therefore be stored together into a single container variable such as the cell array that Andrei used.

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更多回答（2 个）

KL
KL 2017-8-30
N = [B.' C.';
D.' E.'];
F = A+N
Why E has only 3 elements? I'd assume you missed out something there.
  1 个评论
ha ha
ha ha 2017-8-30
编辑：ha ha 2017-8-30
Yes. E should have 4 element (sorry I omitted it). please see my edit question

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Guillaume
Guillaume 2017-8-30
In your particular example, and assuming that E is supposed to have 4 elements instead of the 3 you've written:
F = A + [B.', C.'; D.', E.']
I have no idea where you're going with this question, so can't answer in a generic way.

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