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Rename a dictionary key
...dict[new_key] = mydict.pop(old_key)
For an OrderedDict, I think you must build an entirely new one using a comprehension.
>>> OrderedDict(zip('123', 'abc'))
OrderedDict([('1', 'a'), ('2', 'b'), ('3', 'c')])
>>> oldkey, newkey = '2', 'potato'
>>> OrderedDict((newkey if...
What is this operator in MySQL?
I'm working on code written by a previous developer and in a query it says,
9 Answers
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What's the syntax for mod in java
... % 2) == 0)
{
isEven = true;
}
else
{
isEven = false;
}
This can be simplified to a one-liner:
isEven = (a % 2) == 0;
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How does lucene index documents?
I read some document about Lucene; also I read the document in this link
( http://lucene.sourceforge.net/talks/pisa ).
4 An...
Why is the use of tuples in C++ not more common?
Why does nobody seem to use tuples in C++, either the Boost Tuple Library or the standard library for TR1? I have read a lot of C++ code, and very rarely do I see the use of tuples, but I often see lots of places where tuples would solve many problems (usually returning multiple values from functi...
“Comparison method violates its general contract!”
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Your comparator is not transitive.
Let A be the parent of B, and B be the parent of C. Since A > B and B > C, then it must be the case that A > C. However, if your comparator is invoked on A and C, it would return zero, meaning A == C. This violates the con...
MySQL, update multiple tables with one query
I have a function that updates three tables, but I use three queries to perform this. I wish to use a more convenient approach for good practice.
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Split string based on a regular expression
I have the output of a command in tabular form. I'm parsing this output from a result file and storing it in a string. Each element in one row is separated by one or more whitespace characters, thus I'm using regular expressions to match 1 or more spaces and split it. However, a space is being inser...
How do I count unique values inside a list
... the user for input and store the values in an array / list.
Then when a blank line is entered it will tell the user how many of those values are unique.
I'm building this for real life reasons and not as a problem set.
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How to concatenate columns in a Postgres SELECT?
I have two string columns a and b in a table foo .
8 Answers
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