Count unique categorical values in table
18 views (last 30 days)
Show older comments
My table consist of only categorical values. I try to find unique elements and how many times do they appear in my table. Not my actual data but following can be used instead:
LastName = {'Smith';'Johnson';'Williams';'Jones';'Brown'};
Age = [38;43;38;40;49];
FirstName = {'Amanda' ;'Brenda';'Carl'; 'Denis'; 'Ethan'};
Something = {'String1' ;'String2';'String2'; 'String1'; 'String5'};
Weight = [176;163;131;133;119];
FavoriteColor = {'blue' ;'red' ;'yellow'; 'orange' ;'colorblind' };
T = table(Age,FirstName,Weight,FavoriteColor,Something,'RowNames',LastName)
T.FavoriteColor= categorical(T.FavoriteColor);
T.Something= categorical(T.Something);
I think It is similar to the idea of applying a histogram function so I tried it as well but the data being categorical makes it hard. Could you help?
2 Comments
Accepted Answer
Mohammad Abouali
on 25 Oct 2014
something like this:
First your code to generate sample data:
LastName = {'Smith';'Johnson';'Williams';'Jones';'Brown'};
Age = [38;43;38;40;49];
FirstName = {'Amanda' ;'Brenda';'Carl'; 'Denis'; 'Ethan'};
Something = {'String1' ;'String2';'String2'; 'String1'; 'String5'};
Weight = [176;163;131;133;119];
FavoriteColor = {'blue' ;'red' ;'yellow'; 'orange' ;'colorblind' };
T = table(Age,FirstName,Weight,FavoriteColor,Something,'RowNames',LastName)
T.FavoriteColor= categorical(T.FavoriteColor);
T.Something= categorical(T.Something);
now getting the unique values
unqValue=unique(T.Something);
Now counting
n=arrayfun(@(x) sum(T.Something==x),unqValue);
Now plotting
bar(n)
Now first changing the unqValue from categorical to Cell array and then adding it as labels to the bar chart
unqValueCell=arrayfun(@(x) char(x(1)),unqValue,'UniformOutput',false);
set(gca,'XTickLabel',unqValueCell)
Here is the bar chart:
0 Comments
More Answers (2)
Image Analyst
on 25 Oct 2014
For some reason you chose to use the original poster's code which he said wasn't working rather than either of the two answers that worked. Why? Why not try to use one of the scripts that worked?
3 Comments
Image Analyst
on 25 Oct 2014
What he needed was the histogram. Both answers had that but his original code did not . You can use one of the Answers or try Azzi's code here.
Azzi Abdelmalek
on 25 Oct 2014
Look at this example
LastName = {'Smith';'Johnson';'Williams';'Jones';'Brown'};
Age = [38;43;38;40;40];
Height = [71;69;64;67;64];
Weight = [176;163;131;133;119];
BloodPressure = [124 93; 109 77; 125 83; 117 75; 122 80];
tNonNumeric = table(Age,Height,Weight,BloodPressure,'RowNames',LastName)
%---------------------------------------------------------------------------
a=tNonNumeric.Age
[uniq,jj,kk]=unique(a)
freq=histc(kk,1:numel(uniq))
out=[uniq freq]
7 Comments
Azzi Abdelmalek
on 25 Oct 2014
What is your question for the new example? what column? the first? or all the columns at the same time?
See Also
Categories
Find more on Data Preprocessing 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!