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pandas GroupBy columns with NaN (missing) values
...ore doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1).groupby('b').sum()
Out[12]:
a
b
-1 2
4 1
6 3
That said, this feels pretty awful hack... perhaps there should be an option to include NaN in groupby (see this g...
Explain the “setUp” and “tearDown” Python methods used in test cases
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answered Jul 28 '11 at 6:08
Artsiom RudzenkaArtsiom Rudzenka
22.3k33 gold badges3030 silver badges4747 bronze badges
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What is the recommended batch size for SqlBulkCopy?
...t 6M qualified rows, averaging 5 columns of decimal and short text, about 30 bytes per row.
Given this scenario, I found a batch size of 5,000 to be the best compromise of speed and memory consumption. I started with 500 and experimented with larger. I found 5000 to be 2.5x faster, on average, tha...
RedHat 6 双网卡 TEAM - 更多技术 - 清泛网 - 专注C/C++及内核技术
RedHat 6 双网卡 TEAMMode0 : Round-robin策略：按顺序传输数据包，从第一个可用的slave到最后一个可用的slave。该模式提供了负载均衡和容错机制。Mode1: Act...Mode0 : Round-robin策略：按顺序传输数据包，从第一个可用的slave到最后一个可用...
How to make overlay control above all other controls?
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+50
If you are using a Canvas or Grid in your layout, give the control to be put on top a higher ZIndex.
From MSDN:
<Page xmlns="http...
PowerShell: Store Entire Text File Contents in Variable
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answered Nov 2 '11 at 7:01
manojldsmanojlds
248k5454 gold badges425425 silver badges395395 bronze badges
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How to monitor the memory usage of Node.js?
... node-memwatch does not seem to be alive any more (last updated in March 2013). Are there any alternatives?
– Golo Roden
Feb 10 '15 at 13:00
6
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What exactly happens when I set LoadUserProfile of IIS pool?
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– David d C e Freitas
Jun 5 '14 at 0:29
3
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WPF Bind to itself
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John Cummings
1,30233 gold badges1515 silver badges2626 bronze badges
answered Dec 15 '09 at 10:49
HeinziHeinzi
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Rails: Adding an index after adding column
...ils generate migration AddIndexToTable ?
– user1611830
Apr 8 '13 at 14:32
3
Yes you can do that, ...