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Instance variable: self vs @
...le, you might have a MiddleAgedSocialite class that always reports its age 10 years younger than it actually is. Or more practically, a PersistentPerson class might lazily read that data from a persistent store, cache all its persistent data in a hash.
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what is the most efficient way of counting occurrences in pandas?
I have a large (about 12M rows) dataframe df with say:
3 Answers
3
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How to get multiple counts with one SQL query?
...stributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
share
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Ignoring a class property in Entity Framework 4.1 Code First
...ng(modelBuilder);
}
http://msdn.microsoft.com/en-us/library/hh295847(v=vs.103).aspx
The version I checked is EF 4.3, which is the latest stable version available when you use NuGet.
Edit : SEP 2017
Asp.NET Core(2.0)
Data annotation
If you are using asp.net core (2.0 at the time of this writing), ...
“icon-bar” in twitter bootstrap navigation bar
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130
icon-bar is used for responsive layouts to create a button that looks like ≡ on narrow brows...
Git: Remove committed file after push
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145
update: added safer method
preferred method:
check out the previous (unchanged) state of yo...
Why do you need to create a cursor when querying a sqlite database?
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61
Just a misapplied abstraction it seems to me. A db cursor is an abstraction, meant for data set ...
How to return dictionary keys as a list in Python?
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1070
Try list(newdict.keys()).
This will convert the dict_keys object to a list.
On the other ha...
how to permit an array with strong parameters
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edited Nov 24 '19 at 19:38
Yarin
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