how is it possible to remove all the cells??

is there a way to clear all the cell arrays at the beginning of the code like the way we do it for variables with clear all? if it is possible i do not want to clear each cell one by one like a{:} = {[]}; is there a way to remove all at once ? regards

[hmi amid]

But clear all removes everything! Including cells.

[Rik]

First off, never use clear all, use clear variables instead.

Now to your question. Is there a reason you can't just overwrite your variable with something like C=cell(size(C));?

[samicorp]

@Rik Wisselink that is how you preallocate the cell but my question was how can i remove them all. as @hmi amid mentioned correctly clear all or clear variable would do the job which i did not pay attention to.

Answer 1

[Image Analyst]

Use the command

varInfo = whos

by examining the varinfo structure, you can determine which variables are cell arrays. For example, when I called it when I had 11 variables in existence:

varInfo = 
  11×1 struct array with fields:
    name
    size
    bytes
    class
    global
    sparse
    complex
    nesting
    persistent

Loop over all elements in the structure array and if you find a cell array, initialize it.

for k = 1 : length(varInfo)
    if strcmpi(varInfo(k).class, 'cell')
        % It's a cell array - initialize it
    end
end

Frankly, it might be less complicated just to assign the known names of cell arrays to something. I mean, you know the names in your program, don't you?

[samicorp]

i have already done that. the best way is to assign them one by one. although your way of assigning is also interesting. another question is that since i am working with quite large number of cells what is the fastest way of looping over all these cells? any example would be highly appreciated.

[Image Analyst]

I'm not sure what you're asking. I showed you how to find all the variables in your workspace that are cells or cell arrays (arrays of cells). And I show you how to loop over all of those. Or are you asking how to loop and visit every cell that is one element of a cell array?

Not sure you know what a cell is completely. See the FAQ for a discussion that should give you a good intuitive feel for what they are and how to use them. http://matlab.wikia.com/wiki/FAQ#What_is_a_cell_array.3F

Answer 2

[Jan]

Do not use clear all, because it does not only clear variables, but removed all loaded functions from the memory also. reloading them from the slow hard disk wastes a lot of time.

Using a general method to clear variables is not clean also. Better create functions for your codes, such that the workspace is kept clean.

[samicorp]

Thanks for the input. will do it from now on.