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Convert date to datetime in Python
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answered Dec 21 '09 at 0:33
kiamlalunokiamlaluno
23.5k1515 gold badges6868 silver badges8282 bronze badges
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How do I get SUM function in MySQL to return '0' if no values are found?
... as table_name,
'mixed null/non-null' as description,
21 as expected_sum,
COALESCE(SUM(val), 0) as actual_sum
FROM foo
UNION ALL
SELECT 'bar' as table_name,
'all non-null' as description,
21 ...
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 than ...
python tuple to dict
...gill
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8
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Converting a column within pandas dataframe from int to string
...esult back:
df['A'] = df['A'].apply(str)
Convert the whole frame
In [21]: df.applymap(str)
Out[21]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [22]: df.applymap(str).iloc[0,0]
Out[22]: '0'
df = df.applymap(str)
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Apply a function to every row of a matrix or a data frame
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edited Nov 21 '10 at 4:14
answered Nov 21 '10 at 4:05
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How do I set a column value to NULL in SQL Server Management Studio?
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answered Jan 14 '09 at 21:05
Jeff MartinJeff Martin
9,50566 gold badges4343 silver badges6767 bronze badges
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Regular expression search replace in Sublime Text 2
...$0?
– Skylar Saveland
Mar 30 '13 at 21:58
11
No, $0 is not used as a back-reference in a regular ...
How to find list intersection?
...ates afaict.
– javadba
Jan 6 '19 at 21:53
add a comment
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How to validate an Email in PHP?
...r filter_var ?
– Istiaque Ahmed
Nov 21 '12 at 9:31
3
@kapa, Actually you don't need any more to c...