Saving and Loading variables in Matlab Drive/Matlab Online

I'm working on Matlab Online with files in Matlab Drive. If I save a file

A = [1,2,3,4,5];
save vari A

vari.mat appears in the working folder on Matlab Drive.

I need to load and save files from other folders within Matlab Drive, could someone tell me how this is done please?

I've made a few basic guesses, e.g. made a subfolder testsub, but get

A = [1,2,3,4,5];
save /testsub/vari A

Error using save
Cannot create 'vari.mat' because '/testsub' does not exist.

Answer 1

[Stephen]

Ah, after some more fiddling I realised the leading '/' should not be there.

A = [1,2,3,4,5];
save testsub/vari A

Everything works fine now.