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How do I save and restore multiple variables in python?
I need to save about a dozen objects to a file and then restore them later.
I've tried to use a for loop with pickle and shelve but it didn't work right.
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Definition of a Balanced Tree
I am just wondering if someone might be able to clarify the definition of a balanced tree for me. I have that "a tree is balanced if each sub-tree is balanced and the height of the two sub-trees differ by at most one.
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Python date string to date object
How do I convert a string to a date object in python?
7 Answers
7
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How do MySQL indexes work?
...ally, how can they return the data requested without scanning the entire table?
8 Answers
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How to colorize diff on the command line?
... it augments the output using colored syntax highlighting to increase readability:
diff old new | colordiff
or just:
colordiff old new
Installation:
Ubuntu/Debian: sudo apt-get install colordiff
OS X: brew install colordiff or port install colordiff
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MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Get individual query parameters from Uri [duplicate]
I have a uri string like: http://example.com/file?a=1&b=2&c=string%20param
9 Answers
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Linq to Entities join vs groupjoin
I have web searched but I still cant find a simple answer. Can someone please explain (in simple English) what a GroupJoin is? How is it different from a regular inner Join ? Is it commonly used? Is it only for method syntax? What about query syntax? A c# code example would be nice.
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Use of *args and **kwargs [duplicate]
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The syntax is the * and **. The names *args and **kwargs are only by convention but there's no hard requirement to use them.
You would use *args when you're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your functi...
Difference between numpy.array shape (R, 1) and (R,)
In numpy , some of the operations return in shape (R, 1) but some return (R,) . This will make matrix multiplication more tedious since explicit reshape is required. For example, given a matrix M , if we want to do numpy.dot(M[:,0], numpy.ones((1, R))) where R is the number of rows (of co...