[Tutor] Ummmmmm, suggestions please?

[Joseph J. Strout]

At 5:29 AM -0700 06/16/99, Kenneth M. Power wrote:

>What I want is to accumulate like items into a group. Thus by putting
>two (2) boxes into my Inven(tory), I would get this result:
>
>room1.show()
>Item        Volume
>Box(2)    10			#Or something similar
>Total Volume: 10
>
>Any suggestions on how to accomplish this?

This is what dictionaries are for.  Each unique key in a dictionary maps to
some value.  Basically, try this (untested code):

    def show(self):
	qtys = {}	# empty dictionary mapping items to qty of that item
	totals = {}	# empty dictionary mapping items to their total volume
	for item in self.contents:
	    if item in qtys.keys():
		# something we've seen already!
		qtys[item] = qtys[item] + 1
		totals[item] = totals[item] + item.cube
	    else:
		# not something we've seen already
		qtys[item] = 1
		totals[item] = item.cube
	# now we have totals, print 'em out
	for item in qtys.keys():
	    print "%s(%d)\t\t%f" % (item.name, qtys[item], totals[item])

If you don't want a (1) after single items, then you'll need to use an if
statement to get you to a different print format.

If anything in the above isn't clear, just let me know...

Cheers,
-- Joe
,------------------------------------------------------------------.
|    Joseph J. Strout           Biocomputing -- The Salk Institute |
|    joe@strout.net             http://www.strout.net              |
`------------------------------------------------------------------'