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How to group dataframe rows into list in pandas groupby?
...'A','A','B','B','B','C'], 'b':[1,2,5,5,4,6]})
df
Out[1]:
a b
0 A 1
1 A 2
2 B 5
3 B 5
4 B 4
5 C 6
In [2]: df.groupby('a')['b'].apply(list)
Out[2]:
a
A [1, 2]
B [5, 5, 4]
C [6]
Name: b, dtype: object
In [3]: df1 = df.groupby('a')['b'].apply(list).reset_in...
What do 'lazy' and 'greedy' mean in the context of regular expressions?
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Mibac
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answered Feb 20 '10 at 6:22
SampsonSampson
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Quick easy way to migrate SQLite3 to MySQL? [closed]
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Here is a list of converters (not updated since 2011):
https://www2.sqlite.org/cvstrac/wiki?p=ConverterTools (or snapshot at archive.org)
An alternative method that would work nicely but is rarely mentioned is: use an ORM class that abstracts specific database differen...
What makes a keychain item unique (in iOS)?
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+50
The primary keys are as follows (derived from open source files from Apple, see Schema.m4, KeySchema.m4 and SecItem.cpp):
For a keyc...
Regular expression to find URLs within a string
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edited Aug 26 '15 at 11:00
nhahtdh
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answe...
ASP.NET MVC How to convert ModelState errors to json
...te
where item.Value.Errors.Any()
select item.Value.Errors[0].ErrorMessage).ToList();
EDIT: You can extract multiple errors into separate list items by adding a from clause, like this:
var errorList = (from item in ModelState.Values
from error in item.Errors
select...
Is cout synchronized/thread-safe?
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106
The C++03 standard does not say anything about it. When you have no guarantees about the thread...
Python UTC datetime object's ISO format doesn't include Z (Zulu or Zero offset)
...e zone info by default, and without it, Python actually violates the ISO 8601 specification (if no time zone info is given, assumed to be local time). You can use the pytz package to get some default time zones, or directly subclass tzinfo yourself:
from datetime import datetime, tzinfo, timedelta
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Mocking Extension Methods with Moq
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Aug 23 '11 at 6:20
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Git Cherry-pick vs Merge Workflow
... had a colleague who had 3 months worth of changes to merge, and got some 9000 conflicts in 250000 line code-base. What we did to fix is do the merge one month's worth at a time: conflicts do not build up linearly, and doing it in pieces results in far fewer than 9000 conflicts. It was still a lot...