The easiest way to do this is with accumarray:
a = fileread('GreatExpectations.txt');
w = regexpi(a, ' ', 'split');
[v,~,ic] = unique(w);
counts = accumarray(ic, 1);
imx = find(counts == max(counts));
imn = find(counts == min(counts));
fprintf(1,'\n\tMost frequent: “%s” appears %d times\n', v{imx}, counts(imx))
fprintf(1,'\n\tThere are %d that only appear one time\n\n', length(imn))
I used find rather than the second output of max and min because they only return the first index of the occurrence of the maximum or minimun while find returns them all.
The code produces:
Most frequent: “the” appears 25 times
There are 188 that only appear one time
