How do I collapse sections in Matlab 2017b?

Since upgrading to 2017b (Mac OS 10.11), I can't collapse sections of code. In earlier version of Matlab, there would be a small '-' symbol next to the %% which would allow for the section to be collapsed (and, when collapsed, a '+' symbol to expand). If I open the same code in the older version (2015b), the collapse/expand functionality is still there. Does it exist in 2017b?

%%Import Data
data = csvread('datafile.CSV');  
date='2017_11_09_2';

%%Assign columns  
D=data(:,1);   
T_C=data(:,2);
T=T_C+273.15;  
yield=data(:,3);

Answer 1

[Steven Lord]

You had probably set the Code Folding preferences to allow you to fold Sections in the older release but that preference is not set in the newer release. See also the Code Folding section on this documentation page.

[KTRO]

Yes! Thank you! I was hunting for this box to check.