1

I'm reading some Python code in a library:

(prev_blen, parent.branch_length) = (parent.branch_length, prev_blen - outgroup.branch_length)

And I notice that pref_blen in the l.h.s tuple is assigned the first result of the r.h.s tuple, but pref_blen is then used in the second part of the r.h.s tuple.

Is 'prev_blen' changed to 'parent.branch_length', before 'prev_blen - out group.branch_length' or is the previous value assigned to pref_blen still used? I guess this can be rephrased as, in this code line is the first element of the tuple executed before the second and so on?

Thanks, Ben.

user2864740
  • 60,010
  • 15
  • 145
  • 220
SJWard
  • 3,629
  • 5
  • 39
  • 54

0 Answers0