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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
I have a pandas DataFrame and I want to delete rows from it where the length of the string in a particular column is greater than 2.
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Why should I not wrap every block in “try”-“catch”?
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A method should only catch an exception when it can handle it in some sensible way.
Otherwise, pass it on up, in the hope that a method higher up the call stack can make sense of it.
As others have noted, it is good practice to have an unhandled exception handler (with loggin...
Android screen size HDPI, LDPI, MDPI [duplicate]
... that I need fit in all screen sizes. I have three folders, hdpi , ldpi and mdpi for drawables, but in the emulator there isn't any referense to what resolution hdpi is and what mdpi and ldpi are.
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Set Viewbag before Redirect
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I would like to complete the answer because I am using it and I faced a small problem that is when the TempData is empty for some reason (in my case I only have a message when a conversion is made). So I had to had the test if(TempData["Message"] != null) to avoid an error.
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Padding or margin value in pixels as integer using jQuery
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FYI: jQuery does add the 'px', so Ian's solution works and will also return an integer when passed into parseInt() -- and it doesn't require a plugin: parseInt($('a').css('margin-top').replace('px', ''))
– Peter Rust
Jan 23 '11 at 0:55
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Are foreign keys really necessary in a database design?
... ON DELETE CASCADE. This means that if you have one table containing users and another containing orders or something, then deleting a user could automatically delete all orders that point to that user.
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Run certain code every n seconds [duplicate]
...at case you'd better set t = threading.Timer &c, then t.daemon = True, and only then t.start() right before the print "Hello, World!".
– Alex Martelli
Aug 3 '10 at 5:46
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Checking if a variable is not nil and not zero in ruby
I am using the following code to check if a variable is not nil and not zero
18 Answers
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Clearing a string buffer/builder after loop
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Ah, I think sb.setLength(0); is cleaner and more efficient than declaring it inside the loop. Your solution goes against the performance benefit of using StringBuffer...
– Jon
Feb 11 '10 at 5:38
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?? Coalesce for empty string?
Something I find myself doing more and more is checking a string for empty (as in "" or null) and a conditional operator.
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