How do i check for empty cells within a list

How do i check for empty cells within list? I have a list of cells, namelist, and it has 12 values, i need to check if some of the cells are empty. Thanks

Answer 1

[the cyclist]

It is not clear what you mean by a "list of cells". Can you provide some code that illustrates what types of variables you are using? For example, by "cells", do you mean cell arrays?

Without more details, it is hard to answer your question, but there are functions isempty() and cellfun() that might be useful to you.

Edited in response to your comments:

 >> cellfun(@isempty,namelist)

does what I think you want. For example:

namelist = cell(2,6)
namelist{1} = 'abc'
namelist{12} = 3
cellfun(@isempty,namelist)

[Andy]

i just did

namelist = cell(2,6)

[Andy]

so now i am trying to check the different contents in the namelist thingy. so i want to do something like:

empty?((namelist(1,1))

and have the program return a 1 or 0, so i need to know what to put in place of empty?

[Andy]

is empty check for the whole list though, i just need to check individuals inside the list

[Jan]

cellfun('isempty') is much faster than cellfun(@isempty). The first version checks the number of elements directly in the Mex function, the later calls Matlab by mexCallMATLAB for each element.

[Thumree Sarkar]

This solution is faster and easier...

[Jan]

[EDITED, moved from flag to comment] LULU XUE wrote:

It's very useful!! inspiring！ Thanks

[WANG Jason]

This solution shows the power of Matrix:)

Answer 2

[topdawgnate]

Use the isempty function http://www.mathworks.com/help/techdoc/ref/isempty.html

%Build Cell array (note the curly brackets)

    A{1,1} = [1 4 3; 0 5 8; 7 2 9];
    A{1,2} = 'Anne Smith';
    A{2,1} = 3+7i;
    A{2,2} = [];

Use the isempty function

    isempty(A{2,2}) %Note the difference "{" and "(" brackets

This function will return 1.

Hope this helps. Nate

[Andy]

exactly what i needed, thanks!

[the cyclist]

Be aware that this solution checks a single element within a cell array. My solution checks every element in the cell array individually, and reports whether each cell is empty or not. That might be more efficient, depending on your application.

Answer 3

[Korosh Agha Mohammad Ghasemi]

To check for empty cells within a cell array in MATLAB, you can use the cellfun function combined with isempty. This approach is efficient and straightforward. Here’s how you can do it:

% Example cell array
namelist = {'John', [], 'Alice', 'Bob', [], 'Eve', 'Charlie', [], 'Dave', [], 'Frank', 'Grace'};

% Use cellfun with isempty to find empty cells
emptyCells = cellfun(@isempty, namelist);

% Display the indices of empty cells
emptyIndices = find(emptyCells);

disp('Empty cell indices:');
disp(emptyIndices);

This code will create a logical array emptyCells where each element is true if the corresponding cell in namelist is empty and false otherwise. The find function then returns the indices of the empty cells.

If you prefer a faster implementation, especially for large cell arrays, you can use the string form of cellfun:

emptyCells = cellfun('isempty', namelist);
emptyIndices = find(emptyCells);

disp('Empty cell indices:');
disp(emptyIndices);