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Split list into multiple lists with fixed number of elements
...an iterator, but you can convert the result to a list,
scala> List(1,2,3,4,5,6,"seven").grouped(4).toList
res0: List[List[Any]] = List(List(1, 2, 3, 4), List(5, 6, seven))
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MySQL Insert into multiple tables? (Database normalization?)
...and put that $var in all the MySQL commands?"
Let me elaborate: there are 3 possible ways here:
In the code you see above. This
does it all in MySQL, and the
LAST_INSERT_ID() in the second
statement will automatically be the
value of the autoincrement-column
that was inserted in the first
stateme...
What is the difference between old style and new style classes in Python?
...the method
resolution order in case of multiple inheritance.
Python 3 only has new-style classes.
No matter if you subclass from object or not, classes are new-style
in Python 3.
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How to get indices of a sorted array in Python
...gt;> import numpy
>>> numpy.argsort(myList)
array([0, 1, 2, 4, 3])
http://docs.scipy.org/doc/numpy/reference/generated/numpy.argsort.html
This returns the arguments that would sort the array or list.
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Use of *args and **kwargs [duplicate]
...
1693
The syntax is the * and **. The names *args and **kwargs are only by convention but there's no ...
What is the most efficient/elegant way to parse a flat table into a tree?
...id, descendant_id) VALUES
(1,1), (1,2), (1,4), (1,6),
(2,2), (2,4),
(3,3), (3,5),
(4,4),
(5,5),
(6,6);
Now you can get a tree starting at node 1 like this:
SELECT f.*
FROM FlatTable f
JOIN ClosureTable a ON (f.id = a.descendant_id)
WHERE a.ancestor_id = 1;
The output (in MySQL c...
What would cause an algorithm to have O(log n) complexity?
...o have that log2 16 = 4. Hmmm... what about 128?
128 / 2 = 64
64 / 2 = 32
32 / 2 = 16
16 / 2 = 8
8 / 2 = 4
4 / 2 = 2
2 / 2 = 1
This took seven steps, and log2 128 = 7. Is this a coincidence? Nope! There's a good reason for this. Suppose that we divide a number n by 2 i times. Then...
How to insert newline in string literal?
...
323
Well, simple options are:
string.Format:
string x = string.Format("first line{0}second line...
Flatten nested dictionaries, compressing keys
...;> flatten({'a': 1, 'c': {'a': 2, 'b': {'x': 5, 'y' : 10}}, 'd': [1, 2, 3]})
{'a': 1, 'c_a': 2, 'c_b_x': 5, 'd': [1, 2, 3], 'c_b_y': 10}
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Newline in markdown table?
...
364
Use <br> to force a line break within a table cell.
Markdown Extra and MultiMarkdown al...