# how many times is a value repeated in a table

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Fedi Chaarana on 14 Jul 2021
Hello
I have a mdf4 datei that i read with matlab and was converted into timetable. I converted this timetable to a normal table and i want to analyse the values of the first row. Each values was taken after 0,1s so and are one of these following possibilities{20,50,100} with some tolerance.
My question: how can i create a loop that tells me for how many times a values is repeated on the table ?

Sulaymon Eshkabilov on 14 Jul 2021
N20=sum(tab.prob(:,1)==20); % Times of 20s
N50=sum(tab.prob(:,1)==50); % Times of 50s
N100=sum(tab.prob(:,1)==100); % Times of 100s

Ive J on 14 Jul 2021
You can play with groupSummary which offers lots of options:
tab = table(repmat([20; 50; 100], 20, 1), string((1:60).'), 'VariableNames', {'prob', 'id'});
ans = 8×2 table
prob id ____ ___ 20 "1" 50 "2" 100 "3" 20 "4" 50 "5" 100 "6" 20 "7" 50 "8"
tabSum = groupsummary(tab, 'prob')
tabSum = 3×2 table
prob GroupCount ____ __________ 20 20 50 20 100 20