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Are delphi variables initialized with a value by default?
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10 Answers
10
Active
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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id...
How to Set Focus on Input Field using JQuery
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edited Jul 18 '11 at 20:27
answered Jul 18 '11 at 20:08
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What are paramorphisms?
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110
Yes, that's para. Compare with catamorphism, or foldr:
para :: (a -> [a] -> b -> b) -...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
I have SQL Server 2008 R2 and I want to set a unique column.
4 Answers
4
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Escaping quotes and double quotes
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60
Escaping parameters like that is usually source of frustration and feels a lot like a time waste...
Modular multiplicative inverse function in Python
...meone will find this useful (from wikibooks):
def egcd(a, b):
if a == 0:
return (b, 0, 1)
else:
g, y, x = egcd(b % a, a)
return (g, x - (b // a) * y, y)
def modinv(a, m):
g, x, y = egcd(a, m)
if g != 1:
raise Exception('modular inverse does not exist...
CSS: How to have position:absolute div inside a position:relative div not be cropped by an overflow:
...#box2 { position: absolute }
#box3 { position: absolute; top: 10px }
/* Styling */
#box1 { background: #efe; padding: 5px; width: 125px }
#box2 { background: #fee; padding: 2px; width: 100px; height: 100px }
#box3 { background: #eef; paddi...
Turn off spell checking in Eclipse for good
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edited Jun 20 at 9:12
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111 silver badge
answered Jun 9 '11 at 15:13
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How to do Mercurial's 'hg remove' for all missing files?
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answered Mar 9 '10 at 20:35
mfperzelmfperzel
4,69511 gold badge1414 silver badges1313 bronze badges
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