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Python group by
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Python's built-in itertools module actually has a groupby function , but for that the elements to be grouped must first be sorted such that the elements to be grouped are contiguous in the list:
from operator import itemgetter
sortkeyfn = itemgetter(1)
input = [(...
How to get a random number in Ruby
...6). A roll in craps could be simulated with 2 + rand(6) + rand(6).
Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug,...
How to export query result to csv in Oracle SQL Developer?
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@topr Use method 1, then select all, copy and paste into a text editor and save as csv. You might even be able to paste directly into Excel, but I'm not sure about that.
– Travis
Jan 3 '14 at 20:08
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CoffeeScript, When to use fat arrow (=>) over arrow (->) and vice versa
When building a class in CoffeeScript, should all the instance method be defined using the => ("fat arrow") operator and all the static methods being defined using the -> operator?
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Setting variable to NULL after free
... int *nPtr=NULL;. Now, I would agree that this would be redundant, with a malloc following right in the next line. However, if there is code between the declaration and the first initialization, somebody might start using the variable even though it has no value yet. If you null-initialize, you get ...
How to call a JavaScript function from PHP?
How to call a JavaScript function from PHP?
10 Answers
10
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How to pass an array within a query string?
...s[]" value="Mercedes">
NOTE: Using field[] for multiple values is really poorly documented. I don't see any mention of it in the section on multi-valued keys in Query string - Wikipedia, or in the W3C docs dealing with multi-select inputs.
UPDATE
As commenters have pointed out, this is ve...
Restore the state of std::cout after manipulating it
...lude <iostream> or #include <ios> then when required:
std::ios_base::fmtflags f( cout.flags() );
//Your code here...
cout.flags( f );
You can put these at the beginning and end of your function, or check out this answer on how to use this with RAII.
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Array extension to remove object by value
...with a protocol extension method.
removeObject() is defined as a method on all types conforming
to RangeReplaceableCollectionType (in particular on Array) if
the elements of the collection are Equatable:
extension RangeReplaceableCollectionType where Generator.Element : Equatable {
// Remove f...
_csv.Error: field larger than field limit (131072)
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The csv file might contain very huge fields, therefore increase the field_size_limit:
import sys
import csv
csv.field_size_limit(sys.maxsize)
sys.maxsize works for Python 2.x and 3.x. sys.maxint would only work with Python 2.x (SO: what-is-sys-maxint-in-python-3)
Update
As Geoff pointed out,...