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Sniper4Life

Mon Apr 13, 2009 5:34 pm


Problems with a Question

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Hey I've been having problems with a certain question and the language which I need to do it in is Python.

This is the question:

Write a program that reads in a file name from the user and tells them what kind of file it is by looking at the extension. Your program must be able to recognize at least 5 different file types.
	e.g. "Dogs.doc" is a Word Document

So how would I do this? I don't understand how to do this because in order to do it you need to basically split the input right? And then perform the operations? I just don't get how to do that. Like...this question has more to do with strings than integers...so its a bit confusing for me...would someone like to clarify for me?


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Insectoid

Mon Apr 13, 2009 5:41 pm


RE:Problems with a Question

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there was another thread with this exact question somewhere....

here: http://compsci.ca/v3/viewtopic.php?t=20527


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BigBear

Mon Apr 13, 2009 5:42 pm


RE:Problems with a Question

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try looking up help(str) in the shell to see what commands are availible


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Tony

Mon Apr 13, 2009 5:46 pm


RE:Problems with a Question

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pattern matching actually.

You are right, it's operations on strings. Given a string, you are asked to find a substring that follows the last dot. Matching the string extension to the full name of a program is just aesthetics.

Keep in mind that I could enter something like "dogs.documents.jpeg" for a file name.


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Insectoid

Mon Apr 13, 2009 5:47 pm


RE:Problems with a Question

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I would search the string backwards, each time adding that letter to the front of the string and stopping when you hit a ".".


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Sniper4Life

Mon Apr 13, 2009 6:22 pm


RE:Problems with a Question

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Could someone actually WRITE the answer to this? I learn welly from actually reading code and trying to understand it. The question is from McKenzie's exercises...so ya. If I could see what the answer to THIS would be, I could learn from it and use it for all his other questions.


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Tony

Mon Apr 13, 2009 6:40 pm


RE:Problems with a Question

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Not quite. My solution would open up a can of warms that are regular expressions

http://www.google.ca/search?hl=en&q=site%3Acompsci.ca/v3%20intitle%3Aregex-tut&meta=


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Sniper4Life

Mon Apr 13, 2009 6:47 pm


RE:Problems with a Question

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darn it...i cant figure it out...like i nvr learned bout strings manipulation or like anything about strings in python...and every time i search it up on google i dont find any relevant information that could help me ><