Removing Elements from Cell Array

Hello, I have a cell array with some differently sized arrays of numbers in some code . This cell array gets Modified in a loop , so the first iteration looks like this :-

a{1}=[6 7];

a{2}=[4 7];

a{3}=[1 9];

a{4}=[1 19];

a{5}=[7 23];

There are some cells which need to disappear. for eg in the next iteration of the loop I want indexes {4} and {5} to go and the cell dimension reduced.

So it becomes this way

a{1}=[6 7];

a{2}=[4 7];

a{3}=[1 9];

Assume that indexes 4 and 5 need to go, I store it in an array temp

    temp = [ 4 5];

Then I wrote this code:-

    for i=1:size(temp,2)
    a{temp(:,i)}={};
  end

This is not producing the desired result ,as the cell a still records {4} and {5} as {}. I want the cell to shrink, like how it is done for rectangular arrays if we give command a(4,:)=[] and a(5,:)=[] , the array a reduces in size.

Is it possible to do that for a cell ??

Answer 1

[Azzi Abdelmalek]

a={[6 7],[4 7],[1 9],[1 19],[7 23]};
temp = [ 4 5]; 
a(temp)=[]

[Jan]

@Ajay: Please note, that Azzi does this in a vectorized form. When you use a FOR loop, removing the 4th cell element will move all subsequent elements to the front, such that removing the cell elements 4 and 5 requires:

a(4) = [];
a(4) = [];  % Not a(5)!

Answer 2

[Ajay]

Thank you for the answer.

So what I understand is that in cell arrays, if you want to access individual elements you could do so by using the flower brackets a{1}, a{2} etc

But when you want to access a vector of indexes it is exactly the same way as you would do for vectors,

in the sense a{2} accesses the contents of the cell whereas a(2) access the cell itself so if you enter a command a(2) =[] it initalises the cell to nothing, (or basically deletes that cell), while a{2} initialises the cell contents to nothing, so the cell is still intact. Is this correct ?