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Drop unused factor levels in a subsetted data frame
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429
All you should have to do is to apply factor() to your variable again after subsetting:
> su...
Bytecode features not available in the Java language
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9 Answers
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SQL Server reports 'Invalid column name', but the column is present and the query works through mana
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answered Aug 31 '11 at 16:59
Nicholas CareyNicholas Carey
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Regular expression to match standard 10 digit phone number
...}\s)?\(?\d{3}\)?[\s.-]\d{3}[\s.-]\d{4}$
Matches the following
123-456-7890
(123) 456-7890
123 456 7890
123.456.7890
+91 (123) 456-7890
If you do not want a match on non-US numbers use
^(\+0?1\s)?\(?\d{3}\)?[\s.-]\d{3}[\s.-]\d{4}$
Update :
As noticed by user Simon Weaver below, if you are als...
Using Python 3 in virtualenv
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edited May 24 '14 at 9:39
answered May 24 '14 at 8:11
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Distinct by property of class with LINQ [duplicate]
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Add default value of datetime field in SQL Server to a timestamp
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349
For modifying an existing column in an existing table:
ALTER TABLE YourTable ADD CONSTRAINT DF_...
Convert NaN to 0 in javascript
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591
You can do this:
a = a || 0
...which will convert a from any "falsey" value to 0.
The "fals...
How can I maximize the editor pane in IntelliJ IDEA?
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295
The closest thing would be to hide all tool windows by invoking the Hide All Tool Windows actio...
Mocking member variables of a class using Mockito
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You need to provide a way of accessing the member variables so you can pass in a mock (the most ...