how to delete rows in cell array

3 views (last 30 days)
In my cell array, i have rows with random letters and numbers and rows where every element is 1.Those rows are randomly generated so i dont know their position. How can i delete every row of 1 without knowing their position?

Accepted Answer

Bruno Luong
Bruno Luong on 4 Nov 2018
Edited: Bruno Luong on 4 Nov 2018
>> A=rand(5,3)
A =
0.3012 0.2259 0.9234
0.4709 0.1707 0.4302
0.2305 0.2277 0.1848
0.8443 0.4357 0.9049
0.1948 0.3111 0.9797
>> A(4,:)=1
A =
0.3012 0.2259 0.9234
0.4709 0.1707 0.4302
0.2305 0.2277 0.1848
1.0000 1.0000 1.0000
0.1948 0.3111 0.9797
>> c = num2cell(A)
c =
5×3 cell array
{[0.3012]} {[0.2259]} {[0.9234]}
{[0.4709]} {[0.1707]} {[0.4302]}
{[0.2305]} {[0.2277]} {[0.1848]}
{[ 1]} {[ 1]} {[ 1]}
{[0.1948]} {[0.3111]} {[0.9797]}
Here is the command to remove row(s) with all 1s
>> c(all(cellfun(@(x) isequal(x,1),c),2),:)=[]
c =
4×3 cell array
{[0.3012]} {[0.2259]} {[0.9234]}
{[0.4709]} {[0.1707]} {[0.4302]}
{[0.2305]} {[0.2277]} {[0.1848]}
{[0.1948]} {[0.3111]} {[0.9797]}
>>
  3 Comments
Bruno Luong
Bruno Luong on 4 Nov 2018
Sure. ISEQUAL is generic MATLAB command that return TRUE if and only if the two objects of the arguments are identical. Examples
>> isequal(3,3)
ans =
logical
1
>> isequal(3,'3')
ans =
logical
0
>> isequal(3,[3 1])
ans =
logical
0
>>
>> isequal(3,'3')
ans =
logical
0
CELLFUN will apply ISEQUAL to each element the cell array, and return a matrix of the same size of C where the element TRUE if the elements c{i,j} is equal to 1.
ALL(xxx,2) will returns the logical vector TF with the length equals to number of rows of logical matrix xxx, and true only if a all the columns of a given row is 1, meaning
TF(i)=TRUE if xxx(i,:) are all TRUE.
The last thing to understand is
c(TF,:)=[]
This command removes all the row of C where TF is TRUE.
Put all this together, it does what you ask for.

Sign in to comment.

More Answers (1)

per isakson
per isakson on 4 Nov 2018
Edited: per isakson on 4 Nov 2018
Try
%%I assume that your cell array is somewhat similar to this one
cac = { 'a','b','c'
[1],[2],[3]
'a','b','c'
[1],[1],[1]
'a','b','c'
[1],[2],[3]
};
is_one = cellfun( @(element) isnumeric(element) && element==1, cac );
is_row_of_ones = all( is_one, 2 );
cac( is_row_of_ones, : ) = []
which outputs
cac =
5×3 cell array
{'a'} {'b'} {'c'}
{[1]} {[2]} {[3]}
{'a'} {'b'} {'c'}
{'a'} {'b'} {'c'}
{[1]} {[2]} {[3]}
and see the Matlab documentation

Categories

Find more on Multidimensional Arrays in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!