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Add matrix to matrix

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ha ha
ha ha on 30 Aug 2017
Edited: Stephen Cobeldick on 1 Sep 2017
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 Comment
Stephen Cobeldick
Stephen Cobeldick on 31 Aug 2017
"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):

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Accepted Answer

Andrei Bobrov
Andrei Bobrov on 30 Aug 2017
Edited: Andrei Bobrov on 30 Aug 2017
B = {B1;B2;B3;B4...;Bi}; % Please create B array.
n = cellfun(@numel,B);
A = [cell2mat(B),repelem((1:numel(n))',n)];
  5 Comments

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More Answers (2)

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

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Guillaume
Guillaume on 30 Aug 2017
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.
  1 Comment
ha ha
ha ha on 30 Aug 2017
please see my edit question

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