On 22/10/13 20:20, Key, Gregory E (E S SF RNA FSF 1 C) wrote:
I understand that a comma in Python is a separator and not an operator. In some of the MatPlotLib examples I see code like this: line1, = ax1.plot(t, y1, lw=2, color='red', label='1 HZ') What does the comma do in an assignment statement?
Caveat: I know nothing about MatPlotLib... But a comma after a name like that usually means its part of a tuple (a single element tuple) so you could rewrite it like: (line1,) = ax1.plot(t, y1, lw=2, color='red', label='1 HZ') But I've no idea why you'd want to do that or why MatPlotLib apparently does. Maybe someone who uses MatPlotLib will reveal all... A wee bit of experimenting suggests ou can use it to unpack a single valued tuple. So presumably ax1.plot() returns a single value tuple. Without the comma line1 would also be a tuple but with the comma it takes on the value inside instead... -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ http://www.flickr.com/photos/alangauldphotos _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
