How to add/append column in an array in a for loop?

Hello, I want to get the array [25 25 25 25 25] as the end value of Batt. However, the loop overwrites and I get [25 25 25]. I can't seem to figure out how to append the n_EVs(2) from the next column.
n_AGs = 2;
n_EVs = [2 3];
for j=1:n_AGs
Batt(1,1:n_EVs(j)) = 25;
end
I specifically want to take the value of n_EVs from the array at each iteration and append the Batt at each iteration. For example:
In the first iteration it should give [25 25]. The second iteration should give [25 25 25 25 25] after appending [0 0 25 25 25] to [25 25].
Would appreciate any help. Best!

 Accepted Answer

Does this do what you want:
n_EVs = [2 3];
n_AGs = length(n_EVs)
Batt = [];
for k = 1 : n_AGs
Batt = [Batt, 25 * ones(1, n_EVs(k))]
end
Output:
n_AGs =
2
Batt =
25 25
Batt =
25 25 25 25 25
And for n_EVs = [2, 3, 5] it gives:
Batt =
25 25
Batt =
25 25 25 25 25
Batt =
25 25 25 25 25 25 25 25 25 25

More Answers (1)

simply without loop:
Batt=repmat(25,1,sum(n_EVs))
%or
Batt=repelem(25,1,sum(n_EVs))
%or
Batt(1:5)=25;
If you want to stick with a loop then:
Batt=zeros(1,sum(n_EVs));
for i = 1:sum(n_EVs) % pfcourse you need to preallocate
Batt(i)=25; % just use linear indexing
end
Note: you only get three elements because your loop runs only till 2 not 5

5 Comments

I specifically want to take the value of n_EVs from the array at each iteration and append the Batt at each iteration. My apologies for not being to the point earlier.
just give an example of your desired output
In the first iteration it should give [25 25]. The second iteration should give [25 25 25 25 25] after appending [0 0 25 25 25] to [25 25] .
Alright try this:
n_EVs = [2 3];
Batt=zeros(1,sum(n_EVs)); % you need to preallocate
n_AGs = 2;
blabla=[n_EVs(1) sum(n_EVs)];
for i = 1:numel(n_EVs)
Batt(1:blabla(i))=25 % just use linear indexing
end
It'll work if n_AGs = 2; but if I change n_AGs = 3; or more it gives error.
For example if I change n_AGs = 3; and n_EVs = [2 3 5];

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Asked:

on 24 Dec 2018

Commented:

on 25 Dec 2018

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