MATLAB: Count occurrences of string in a single cell array (How many times a string appear)

countMATLABoccurrence

I have a single cell array containing long string as shown bellow:

xx = {'computer', 'car', 'computer', 'bus', 'tree', 'car'};

I am trying to achieve output in two cell array as shown:

xx  = {'computer', 'car', 'bus', 'tree'}
occ = {'2', '2','1','1'}

Your suggestion and ideas are highly appreciated. Thanx in advance

Best Answer

xx = {'computer', 'car', 'computer', 'bus', 'tree', 'car'}
a=unique(xx,'stable')
b=cellfun(@(x) sum(ismember(xx,x)),a,'un',0)

Related Solutions

MATLAB: Efficient number occurence count

In this situation, accumarray will be faster than histcounts, but still not as fast as the for-loop,

tic;
hc=accumarray(num(:),1,[mx,1]).';
toc
Elapsed time is 0.172890 seconds. %for-loop

Elapsed time is 0.236013 seconds. %accumarray

unless the values are pre-sorted,

num=sort(num(:));
tic;
hc=accumarray(num(:),1,[mx,1]).';
toc
Elapsed time is 0.168976 seconds. %for-loop
Elapsed time is 0.075965 seconds. %accumarray

I think this is simply one of those situations where Matlab's for-loop optimization has caught up to vectorized code.

MATLAB: Which method to use, basic for loop or loop through values of a vector

x = rand(1, 1e6);
y = zeros(size(x));
ind = randperm(numel(x));
tic
for loop = 1:10
  for k = 1:numel(ind)
      y(ind(k)) = x(ind(k));
  end
end
toc
tic
for loop = 1:10
  for k = ind
      y(k) = x(k);
  end
end
toc
% Elapsed time is 0.395765 seconds.
% Elapsed time is 0.739708 seconds.

The first approach can be handled more efficiently.

Best Answer

Related Solutions

MATLAB: Efficient number occurence count

MATLAB: Which method to use, basic for loop or loop through values of a vector

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