nemorathwald: (thoughts)
nemorathwald ([personal profile] nemorathwald) wrote2009-01-17 05:25 pm

Python Version of My Java Homework

[livejournal.com profile] le_bebna_kamni knows Java really well, which has come in handy for tutoring, I can tell you.

However, she also has a copy of "Beginning Python From Novice To Professional" by Magnus Lie Hetland lying around. Since Python is the language I want to make actual real projects in, I was curious. So I decided to do my homework again, in Python. This time it was six lines long.

However, I decided to take it further. The new version properly uses singular and plural English. In other words, it will say "1 hour" instead of "1 hours."

totalSeconds = input("How many seconds?")
hours = totalSeconds / 3600
remainingSeconds = totalSeconds % 3600
minutes = remainingSeconds / 60
seconds = remainingSeconds % 60

if hours == 1:
   pluralHour = ""
else:
   pluralHour = "s"

if minutes == 1:
   pluralMinute = ""
else:
   pluralMinute = "s"

if seconds == 1:
   pluralSecond = ""
else:
   pluralSecond = "s"

print str(hours) + " hour" + str(pluralHour) + ", " + str(minutes) + " minute" + str(pluralMinute) + ", and " + str(seconds) + " second" + str(pluralSecond) + "."

So while I was doing this, she also did the exercise in Python, except she didn't want to type the singlular/plural decision into her version three times like I did. She felt it was more elegant to make one set of pluralization instructions and have Python repeat it for hours, minutes, and seconds. She cursed at the computer for a half hour and came up with the version she will post in the comments.

I do not curse at the computer. I expect coding to be painful, and have been pleasantly surprised to be proven wrong.

pain = False

if not pain:
    gain = False

[identity profile] loop-bell.livejournal.com 2009-01-18 02:32 am (UTC)(link)
Here's a neat trick I've recently learned in Python for conditional assignments:

This:

if hour == 1:
   pluralHour  = ""
else
   pluralHour = "s"


Is the same as this:
pluralHour = "s" if hour == 1 else ""


I think the second actually shows a little more clearly what is being done, especially in cases like this where the if clause is short. (When the if clause is really long, it tends to make the lines get unreadably long when you do it this way)

In lojban terms, think of it as a sort of SE variety of conditianals -- the x2 gets rotated out to the front and then x1 and x3 follow. Or I also think of it as "inside out" notation, because the part that's normally in the middle comes first.

[identity profile] matt-arnold.livejournal.com 2009-01-18 02:53 am (UTC)(link)
Oh, that's good!