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COUNT DISTINCT with CONDITIONS
I want to count the number of distinct items in a column subject to a certain condition, for example if the table is like this:
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What is the order of precedence for CSS?
I'm trying to figure out why one of my css classes seems to override the other (and not the other way around)
8 Answers
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What is the largest TCP/IP network port number allowable for IPv4?
What is the highest port number one can use?
8 Answers
8
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Iterating over a numpy array
Is there a less verbose alternative to this:
3 Answers
3
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How to center a “position: absolute” element
I'm having a problem centering an element that has the attribute position set to absolute .
Does anyone know why the images are not centered?
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What is a 'semantic predicate' in ANTLR?
What is a semantic predicate in ANTLR?
2 Answers
2
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How to find list of possible words from a letter matrix [Boggle Solver]
Lately I have been playing a game on my iPhone called Scramble. Some of you may know this game as Boggle. Essentially, when the game starts you get a matrix of letters like so:
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Compare version numbers without using split function
How do I compare version numbers?
5 Answers
5
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What is the difference between & and && in Java?
I always thought that && operator in Java is used for verifying whether both its boolean operands are true , and the & operator is used to do Bit-wise operations on two integer types.
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