'Reference to non-existent field'

Hi all. I'm studying this code of exporting surface to STL file. However, MATLAB shows 'Reference to non-existent field 'a'.', which I cannot get it. Can anyone help me with that?

Thanks in advance!

Answer 1

[madhan ravi]

it means your mat file doesn't contain a

[BreakOfDawn]

Yes you're right. I need to think about the meaning of the original code. Thanks!

[madhan ravi]

Anytime :)

[Muhammad Wajahat]

how it remove?