I have this UnboundLocalError
“local variable ‘A’ referenced before assignment”
I am not referencing A before assignment as far as I know. Please talk me through what this actually means. Nobody else seems to have experienced this, so I am doubtless making a rather basic mistake.
You misspelled the variable name A_prev. Dash and underscore are not the same thing. As a result, it interprets that as a subtraction, right? A minus prev. That will not end well.
Apologies for wasting your time. That definitely qualifies as a rather basic mistake.
I have increased the degree of zoom on my browser.