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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
I'm currently trying out Genymotion and boy, it's so much faster than the ADT emulator.
10 Answers
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Detect encoding and make everything UTF-8
I'm reading out lots of texts from various RSS feeds and inserting them into my database.
24 Answers
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Difference between CTE and SubQuery?
...rsions, they are probably very similar. You would have to use the profiler and actual execution plan to spot any differences, and that would be specific to your setup (so we can't tell you the answer in full).
In general; A CTE can be used recursively; a sub-query cannot. This makes them especially...
Convert int to char in java
...onding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int as in ascii value, you can use Character.toChars(48) for example.
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Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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Why does C++ rand() seem to generate only numbers of the same order of magnitude?
In a small application written in C/C++, I am facing a problem with the rand function and maybe the seed :
9 Answers
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Reverse Range in Swift
...here for the bounds.
Earlier edit for Swift 1.2: As of Xcode 6 Beta 4, by and ReverseRange don't exist anymore :[
If you are just looking to reverse a range, the reverse function is all you need:
for i in reverse(1...5) { println(i) } // prints 5,4,3,2,1
As posted by 0x7fffffff there is a new s...
Understanding the map function
Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
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How to redirect output to a file and stdout
In bash, calling foo would display any output from that command on the stdout.
10 Answers
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