categorical bar graph

[Raag Saluja]

Hi! I have to make a bar graph and I want to change the x values to names. I tried the Matlab tutorial as I couldn't find that in octave:

x = categorical ({'small', 'medium', 'large', 'extra large')};

x= reordercats (x, {'small', 'medium', 'large', 'extralarge');

y = [5 20 77 19]

bar(x,y)

However, I got an error message. PFA the screenshot. Can you please help? 

Thank you and regards,

Raag Saluja

Research Scholar

Department of Zoology

Faculty of Science

Dayalbagh Educational Institute

Dayalbagh

Agra

INDIA

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