MATLAB - How to prevent tabulate function returning frequencies of variables that are not present in the vector?

Question

I have the vector v1, with 26 elements, either being 'Live' or 'Non-live'. When I use tabulate(v1), it returns

tabulate(v1)
       Value    Count   Percent
        cat1        0      0.00%
        cat2        0      0.00%
        Live        5     19.23%
    Non-live       21     80.77%

This affects crosstab also. How to prevent tabulate and crosstab functions taking non-existing variables in the vector in to account?

score 0 · Answer 1 · answered Apr 17 '20 at 08:16

0

From the example here it suggests you might get results in tabulate that aren't in your data if your variable isn't categorical. Try converting it to categorical and running tabulate again.

categorical_v1 = categorical(v1);
tabulate(categorical_v1)

It looks like v1 could already be categorical, but perhaps it was not set up correctly, so cat1 and cat2 are remnants of this. "Recategorising" the data should remove these extra categories.

answered Apr 17 '20 at 08:16

Dominic D

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v1 is already categorical. Running categorical function on it again and running tabulate and crosstab still gives the same output. – supun manathunga Apr 17 '20 at 12:56
Can you check the categories of the data by `categories(v1)`? If that returns only `Live` and `Non-live` that suggests it must be a `tabulate` issue. – Dominic D Apr 17 '20 at 22:48
categories(v1) also returns cat1 and cat2 – supun manathunga Apr 18 '20 at 05:43
But `unique(v1)` doesn't contain cat1 and cat2? How about `categories(categorical(v1))`? Or `categories(categorical(v1, {'Live','Non-live'}))`? – Dominic D Apr 18 '20 at 21:42

MATLAB - How to prevent tabulate function returning frequencies of variables that are not present in the vector?

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