How to Pad an Array with extra zeros

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Say I have an array, and I use to reshape function to divide it into equal sections. In the case that it cannot be divided into equal sections, how do I add zeros at the end to compensate? Say A=[1 8 1 9 1 4 1 5 0 4], and I want to divide it into sections of 4. 4 is not a set value.
  1 Comment
Shaquille Powell
Shaquille Powell on 23 Oct 2017
I'm new to this so I keep asking confusing questions. I want the end up with B=[1 8 1 8,1 4 1 5, 0 4 0 0]

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Accepted Answer

Stephen23
Stephen23 on 23 Oct 2017
Edited: Stephen23 on 23 Oct 2017
Here are some simple methods that automatically adjusts to the length of the vector:
Method One: pad to end of vector:
>> A = [1,8,1,9,1,4,1,5,0,4];
>> N = 4;
>> B = A;
>> B(end+1:N*ceil(numel(B)/N)) = 0
B =
1 8 1 9 1 4 1 5 0 4 0 0
Method Two: preallocate a vector of the right size:
>> A = [1,8,1,9,1,4,1,5,0,4];
>> N = 4;
>> B = zeros(1,N*ceil(numel(A)/N));
>> B(1:numel(A)) = A
B =
1 8 1 9 1 4 1 5 0 4 0 0

More Answers (2)

Andrei Bobrov
Andrei Bobrov on 23 Oct 2017
Edited: Andrei Bobrov on 23 Oct 2017
A=[1 8 1 9 1 4 1 5 0 4];
n = 4;
B = reshape([A(:);zeros(mod(-numel(A),n),1)],n,[])';

KSSV
KSSV on 23 Oct 2017
Edited: KSSV on 23 Oct 2017
doc padarray
B = [A zeros(1,2)]

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