satoru wrote: > As to "sample", it never get assigned to and when you say "append" the > class variable is changed in place. > hope my explaination helps.
Sure does, thanks a lot. Here's an interesting side note: After fixing my "Channel" thingy the whole project behaved as expected. But there was an interesting hitch. The main part revolves around another class, "Sequence", which has a list of Channels as attribute. I was curious about the performance of my script, because eventually this construct is supposed to handle megabytes of data. So I wrote a simple loop that creates a new Sequence, fills all the Channels with data, and repeats. Interistingly, the first couple of dozens iterations went satisfactorily quickly (took about 1 second total), but after a hundred or so times it got really slow -- like a couple of seconds per iteration. Playing around with the code, not really knowing what to do, I found that in the "Sequence" class I had again erroneously declared a class-level attribute -- rather harmlessly, just a string, that got assigned to once in each iteration on object creation. After I had deleted that, the loop went blindingly fast without slowing down. What's the mechanics behind this behavior? robert -- http://mail.python.org/mailman/listinfo/python-list