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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...
Importing a CSV file into a sqlite3 database table using Python
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edited May 26 at 0:35
answered May 22 '10 at 12:20
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Select first row in each GROUP BY group?
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On Oracle 9.2+ (not 8i+ as originally stated), SQL Server 2005+, PostgreSQL 8.4+, DB2, Firebird 3.0+, Teradata, Sybase, Vertica:
WITH summary AS (
SELECT p.id,
p.customer,
p.total,
ROW_NUMBER() OVER(PARTITION BY p.customer
...
UIView frame, bounds and center
... among the previous properties:
frame.origin = center - (bounds.size / 2.0)
center = frame.origin + (bounds.size / 2.0)
frame.size = bounds.size
NOTE: These relationships do not apply if views are rotated. For further info, I will suggest you take a look at the following image taken from The Kit...
Remove underline from links in TextView - Android
...
220
+50
You can d...
Installing Bootstrap 3 on Rails App
I'm trying to install Bootstrap 3.0 on my Rails app. I recently finished Michael Hartl's tutorial and am now trying to build my own system using this new version of Bootstrap, but I have a few questions that I'm not sure about.
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What are transparent comparators?
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60
What problem does this solve,
See Dietmar's answer and remyabel's answer.
and does this...
Unresolved specs during Gem::Specification.reset:
...s when running 'gem cleanup' so I found this: stackoverflow.com/questions/4007074/… Turns out it had to do with RVM. When I ran 'rvm gemset use global' and ran guard, the errors went away.
– reneruiz
Aug 8 '13 at 18:54
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Java string split with “.” (dot) [duplicate]
...o split on a literal dot:
String extensionRemoved = filename.split("\\.")[0];
Otherwise you are splitting on the regex ., which means "any character".
Note the double backslash needed to create a single backslash in the regex.
You're getting an ArrayIndexOutOfBoundsException because your input...
XP风格按钮的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...txt改名为 “程序名.manifest”就可以了。
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity name="XP style manifest" processorArchitecture="x86" version="1.0.0.0" type="win32"/>
<depe...