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Python pandas Filtering out nan from a data selection of a column of strings
...
Just drop them:
nms.dropna(thresh=2)
this will drop all rows where there are at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob N...
Best exception for an invalid generic type argument
...ere's a way in which NotSupportedException is obviously good enough, especially given its common-sense meaning. Having said that, I'm not sure if it's just right.
Given the purpose of Unconstrained Melody ...
There are various useful things that can be done with generic
methods/classes where ...
Java Enum Methods - return opposite direction enum
... method that returns the opposite direction (the following is not syntactically correct, i.e, enums cannot be instantiated, but it illustrates my point). Is this possible in Java?
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Polymorphism: Why use “List list = new ArrayList” instead of “ArrayList list = new ArrayList”? [dupl
... code only knows that data is of type List, which is preferable because it allows you to switch between different implementations of the List interface with ease.
For instance, say you were writing a fairly large 3rd party library, and say that you decided to implement the core of your library with...
Spring @Transactional - isolation, propagation
...tion
Defines the data contract between transactions.
Read Uncommitted: Allows dirty reads.
Read Committed: Does not allow dirty reads.
Repeatable Read: If a row is read twice in the same transaction, the result will always be the same.
Serializable: Performs all transactions in a sequence.
The...
What is the difference between “instantiated” and “initialized”?
... it to be. The value is what you assign to it.
Variables are Initialized
All variables are always given an initial value at the point the variable is declared. Thus all variables are initialized.
For value types, like int the compiler will give them a valid value if you do not do so explicitly. i...
Boolean method naming readability
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"makes your {method call} far more like natural english" sounds like a great test for rational naming across the board. clarified my thinking on the matter - thanks!
– cori
Jun 2 '11 at 12:06
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Can I unshelve to a different branch in tfs 2008?
... unshelve /?
tfpt unshelve - Unshelve into workspace with pending changes
Allows a shelveset to be unshelved into a workspace with pending changes.
Merges content between local and shelved changes. Allows migration of shelved
changes from one branch into another by rewriting server paths.
Usage: t...
must appear in the GROUP BY clause or be used in an aggregate function
I have a table that looks like this caller 'makerar'
7 Answers
7
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Best practices for storing postal addresses in a database (RDBMS)?
...veal some nice pearls for interpreting and validating addresses internationally. It also has a nice set of administrative areas ( province, state, oblast, etc ) with ISO codes.
Here's the gist of the schema, copied from the module page:
country => Country (always required, 2 character ISO code...