Could you help me interpret what happened?

Greetings,

I am debugging others' codes. In Polyhedron.m file row 521, it is a sentence:

if isempty(obj.He_int), obj.He_int = zeros(0,d+1); end

I found before this sentence was executed, obj.V was not defined as:

But after this sentence was executed, obj.V was calculated and got a matrix:

As you see, the sentence did not call obj.V directly but it did change obj.V. Could you explain to me what happened here? And how can I find the codes that changed obj.V. I think that is the bug I am looking for.

Related source codes are attached.

Thank you!

Answer 1

[Matt J]

obj.V is a Dependent property.

[Xin Shen]

Thank you, Matt.

Yes, obj.V is denpendent property. So I add breakpoint inside function get.V. But get.V function is never been called in Polyhedron.m file row 521, how does it determine obj.V and how can I change the way to determine obj.V?

[Matt J]

No, there is no reason it would be called in row 521 because V is not accessed there. It is accessed only later, when you try to display V in the variable editor.

[Xin Shen]

Thank you, Sir!

That means I need to revisit get.V function to understand how it calculate obj.V and why obj.V needs He_int. Am I right?

[Matt J]

Yes, I would imagine.

[Xin Shen]

Thank you very much, wish I can find the bug!