# How can I find the second and third, etc. most frequent character in say a list of words (cell array of strings)?

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Rebecca Hussey on 5 Nov 2015
Commented: Walter Roberson on 15 Jun 2020
How can I find the second and third, etc. most frequent character in say a list of words (cell array of strings)?
I know how to find the most frequent in all words: mode(strjoin(dict,'')). However I know want to know how to find the second and third and fourth etc. Dict is my a list of words.

TastyPastry on 5 Nov 2015
a = unique(myStr);
n = histc(myStr,a);
[n,idx] = sort(n);
myFreq = myStr(idx);
Now myFreq will be the unique characters sorted from highest occurring to lowest. The sorted vector n will give you the number of times a character appears in your string. This does assume you've already concatenated all the words using
strjoin(dict,'');
Walter Roberson on 15 Jun 2020
a is the list of unique values in myStr
n is the count of the number of times each unique value in myStr occurs.
Then n is sorted into ascending order, and the sort order is recorded in idx
myFreq then uses the recorded sort order in order to sort the unique values into ascending order according to count.