Count the number of occurrences in a string vector

Hi,

I'm relatively new to Matlab because I only used Excel so far. For my project I used the COUNTIFS function and I'm wondering how to do this in Matlab.

Say I've got a column vector 300x1:

I want to create a vector of the same size that counts and sums up each entry.

Example:

If my entries are A;A;B;A;B;B;C;A;C the new vector should look like: 1;2;1;3;2;3;1;4;2

Thank you so much!

Answer 1

[Andrei Bobrov]

s = string({'A';'A';'B';'A';'B';'B';'C';'A';'C'});

out = zeros(numel(s),1);
[~,~,c] = unique(s);
for i = 1:max(c)
    lo = c == i; 
    out(lo) = 1:sum(lo); 
end

or

[~,~,c] = unique(s);
z = c == (1:max(c)); % or use here: z = bsxfun(@eq,c,1:max(c));
out = sum(cumsum(z).*z,2);

I'm use R2016b.

[buhmatlab]

This works perfectly! I wonder how long it would have taken for me to figure this out...

THANK YOU!!!