string-comparison

I want to write a cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses. Return -1 if version A is older than version B Return 0 if version A and B are equivalent Return 1 if version A is newer than version B Each subsection is supposed to be interpreted as a number, therefore 1.10 > 1.1. Desired function outputs are mycmp('1.0', '1') == 0 mycmp('1.0.0', '1') == 0 mycmp('1', '1.0.0.1') == -1 mycmp('12.10', '11.0.0.0.0') == 1 ... And here is my implementation, open for improvement: def mycmp(version1, version2): parts1 = [int(x) for x in

I fall into a surprising issue. I loaded a text file in my application and I have some logic which compares the value having µ. And I realized that even if the texts are same the compare value is false. Console.WriteLine("μ".Equals("µ")); // returns false Console.WriteLine("µ".Equals("µ")); // return true In later line the character µ is copy pasted. However, these might not be the only characters that are like this. Is there any way in C# to compare the characters which look the same but are actually different? BoltClock In many cases, you can normalize both of the Unicode characters to a

I have a class with an accessible method that passes back an NSString when called. [MyClass getMyString] The string variable in that class is actually assigned in the didSelectRowAtIndexPath: part of a table like this: myString = cell.textLabel.text; When I retrieve the string by calling that method, I assign it to another string in the class that called it and compare it to a string I have defined NSString *mySecondString; mySecondString = @"my value"; if(mySecondString == myString){ i = 9; } I have stepped through the code and every time it evaluates the if statement, it skips right past the

I'm trying to compare a string called facility to multiple possible strings to test if it is valid. The valid strings are: auth, authpriv, daemon, cron, ftp, lpr, kern, mail, news, syslog, user, uucp, local0, ... , local7 Is there an efficient way of doing this other than: if facility == "auth" or facility == "authpriv" ... pillmuncher If, OTOH, your list of strings is indeed hideously long, use a set: accepted_strings = {'auth', 'authpriv', 'daemon'} if facility in accepted_strings: do_stuff() Testing for containment in a set is O(1) on average. Unless your list of strings gets hideously long

This question already has an answer here: About the changing id of an immutable string 5 answers Why does "hello" is "hello" produce True in Python? I read the following here : If two string literals are equal, they have been put to same memory location. A string is an immutable entity. No harm can be done. So there is one and only one place in memory for every Python string? Sounds pretty strange. What's going on here? carl Python (like Java, C, C++, .NET) uses string pooling / interning. The interpreter realises that "hello" is the same as "hello", so it optimizes and uses the same location