Yes! Thankyou. I can't believe I stared at this problem for so long and didn't notice I only went to N in the first loop. I'm not sure why I said N was not known. I meant to say that it was a variable so I couldn't just make all the bands explicitly using the band1, band2, ..., bandN method. Thanks again for your help

Yes! Thankyou. I can't believe I stared at this problem for so long and didn't notice I only went to N in the first loop. I'm not sure why I said N was not known. I meant to say that it was a variable so I couldn't just make all the bands explicitly using the band1, band2, ..., bandN method. Thanks again for your help

Thanks for the help. Am I right in thinking that op(op(HA)[3]) returns the third element of the list op(HA)?

Thanks for the help. Am I right in thinking that op(op(HA)[3]) returns the third element of the list op(HA)?