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Pandas dataframe get first row of each group
...;> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6...
“Unicode Error ”unicodeescape" codec can't decode bytes… Cannot open text files in Python 3 [duplica
I am using python 3.1, on a windows 7 machines. Russian is the default system language, and utf-8 is the default encoding.
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Python, compute list difference
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373
If the order does not matter, you can simply calculate the set difference:
>>> set([...
What is the smallest possible valid PDF?
...lt;/Type/Catalog/Pages 2 0 R>>endobj 2 0 obj<</Type/Pages/Kids[3 0 R]/Count 1>>endobj 3 0 obj<</Type/Page/MediaBox[0 0 3 3]>>endobj
xref
0 4
0000000000 65535 f
0000000010 00000 n
0000000053 00000 n
0000000102 00000 n
trailer<</Size 4/Root 1 0 R>>
startxref
1...
How can I multiply all items in a list together with Python?
...t takes
a list of numbers and multiplies them together. Example:
[1,2,3,4,5,6] will give me 1*2*3*4*5*6 . I could really use your help.
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Joda-Time: what's the difference between Period, Interval and Duration?
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3 classes are needed because they represent different concepts so it is a matter of picking the appropriate one for the job rather than of relative performance. From the documentation with comments added by me in italics:
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Read stream twice
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Captain Man
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answered Feb 29 '12 at 14:59
Paul GrimePaul Grime
...
Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
I have a string that is up to 3 characters long when it's first created in SQL Server 2008 R2.
17 Answers
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Plot a legend outside of the plotting area in base graphics?
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113
Maybe what you need is par(xpd=TRUE) to enable things to be drawn outside the plot region. So if...