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What's the difference between “groups” and “captures” in .NET regular expressions?
...ew value. Not .NET, which will keep this history and places it in Captures[0].
If we change your regex to look as follows:
MatchCollection matches = Regex.Matches("{Q}{R}{S}", @"(\{[A-Z]\})+");
you will notice that the first Group will have one Captures (the first group always being the whole m...
Finding the index of elements based on a condition using python list comprehension
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answered Sep 1 '11 at 13:20
Mike GrahamMike Graham
60.5k1212 gold badges8484 silver badges119119 bronze badges
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What does the constant 0.0039215689 represent?
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0.0039215689 is approximately equal to 1/255.
Seeing that this is OpenGL, performance is probably important. So it's probably safe to guess that this was done for performance reasons.
Multiplying by the reciprocal is faster...
Types in MySQL: BigInt(20) vs Int(20)
...ous that they would allow for larger numbers; however, I can make an Int(20) or a BigInt(20) and that would make seem that it is not necessarily about size.
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Does MSTest have an equivalent to NUnit's TestCase?
... note on an older version of the TestAdapter, which was removed from the 2.0.0's description page:
Note that it doesn't work with VS Express
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A better similarity ranking algorithm for variable length strings
...str1 varchar, str2 varchar)
RETURNS float8 AS '
str1.downcase!
pairs1 = (0..str1.length-2).collect {|i| str1[i,2]}.reject {
|pair| pair.include? " "}
str2.downcase!
pairs2 = (0..str2.length-2).collect {|i| str2[i,2]}.reject {
|pair| pair.include? " "}
union = pairs1.size + pairs2.size
inters...
How do I profile memory usage in Python?
...ex Count % Size % Cumulative % Kind (class / dict of class)
0 25773 53 1612820 49 1612820 49 str
1 11699 24 483960 15 2096780 64 tuple
2 174 0 241584 7 2338364 72 dict of module
3 3478 7 222592 7 2560956 78 types.CodeType
4 3...
Is there any way to prevent input type=“number” getting negative values?
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Use the min attribute like this:
<input type="number" min="0">
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Multiple aggregations of the same column using pandas GroupBy.agg()
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You can simply pass the functions as a list:
In [20]: df.groupby("dummy").agg({"returns": [np.mean, np.sum]})
Out[20]:
mean sum
dummy
1 0.036901 0.369012
or as a dictionary:
In [21]: df.groupby('dummy').agg({'returns':
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how to find host name from IP with out login to the host
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Use nslookup
nslookup 208.77.188.166
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Non-authoritative answer:
166.188.77.208.in-addr.arpa name = www.example.com.
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