On Nov 4, 12:47 am, Dennis Lee Bieber <[EMAIL PROTECTED]> wrote: > On Sat, 03 Nov 2007 21:30:10 -0700, Tom_chicollegeboy > <[EMAIL PROTECTED]> declaimed the following in comp.lang.python: > > > > > It works only for first set. How should I implement another solution > > that would move program to read next set? I think I should implement > > nested while look, with first that reads until -1 and under it another > > while loop that reads n times sets. But I have no idea how. Can you > > help me? > > Homework, huh? So I need to avoid a working solution... > > Personally, based upon the nature of the data file, I'd base the > entire algorithm on a control break which is signified by a line with a > single "term", and ignore the "count" value of that term. > > I'd have to ignore the first "control break" as there is no output > at that time. That can be done by initially setting the total mileage to > None (not to 0). > > On a control break (len(input.split()) == 1): if total mileage is > NOT None, output results; set total mileage and elapsed time to 0. > > On a data line (len(input.split()) == 2): total mileage = total > mileage + speed * (current time - elapsed time); elapsed time = current > time. > > Exit on EOF. > > This algorithm will function even with erroneous input: > > 4 <== only three actual values follow > 20 2 > 30 6 > 10 7 > 2 > 60 1 > 30 5 > -1 > > Calling the function "speed" is misleading too -- the /input/ is > speed and time, but the output wanted is mileage. > > With the following data: > -=-=-=-=-=-=-=- > 4 > 20 2 > 30 6 > 10 7 > 2 > 60 1 > 30 5 > -1 > 10 1 > 25 1 > 5 10 > -=-=-=-=-=-=-=-=- > > A quick program produces the following output (NOTE: I added a LOT > of ouput statements so you can see the logic -- but I won't show the > actual code). > > initialize total None, elapsed 0, trip count 0 > open data file > loop over lines in input file, exit on null line > input line is: [4] > number of values in the line: 1 > one value, control break > no trip data read before this control break > resetting total mileage 0, elapsed 0, incrementing trip count 1 > input line is: [20, 2] > number of values in the line: 2 > elapsed miles: 40 > input line is: [30, 6] > number of values in the line: 2 > elapsed miles: 160 > input line is: [10, 7] > number of values in the line: 2 > elapsed miles: 170 > input line is: [2] > number of values in the line: 1 > one value, control break > trip 1: 170 miles > resetting total mileage 0, elapsed 0, incrementing trip count 2 > input line is: [60, 1] > number of values in the line: 2 > elapsed miles: 60 > input line is: [30, 5] > number of values in the line: 2 > elapsed miles: 180 > input line is: [-1] > number of values in the line: 1 > one value, control break > trip 2: 180 miles > resetting total mileage 0, elapsed 0, incrementing trip count 3 > input line is: [10, 1] > number of values in the line: 2 > elapsed miles: 10 > input line is: [25, 1] > number of values in the line: 2 > elapsed miles: 10 > input line is: [5, 10] > number of values in the line: 2 > elapsed miles: 55 > No terminating control break found > Unfinished trip is: > trip 3: 55 miles > > By the way -- YOUR sample input data has ONLY TWO TRIPS -- so how > can the correct output be THREE trips? > -- > Wulfraed Dennis Lee Bieber KD6MOG > [EMAIL PROTECTED] [EMAIL PROTECTED] > HTTP://wlfraed.home.netcom.com/ > (Bestiaria Support Staff: [EMAIL PROTECTED]) > HTTP://www.bestiaria.com/
very helpful hints. thank you very much -- http://mail.python.org/mailman/listinfo/python-list
