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dplyr: “Error in n(): function should not be called directly”
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edited Jan 27 '15 at 0:44
Michael Bellhouse
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“x not in y” or “not x in y”
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answered Jan 5 '12 at 6:45
BenBen
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Regular expression to limit number of characters to 10
... options are:
{3} Exactly 3 occurrences;
{6,} At least 6 occurrences;
{2,5} 2 to 5 occurrences.
See the regular expression reference.
Your expression had a + after the closing curly brace, hence the error.
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Breaking loop when “warnings()” appear in R
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152
You can turn warnings into errors with:
options(warn=2)
Unlike warnings, errors will interru...
Error: Could not create the Java Virtual Machine Mac OSX Mavericks
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305
Normally this error occurs when you invoke java by supplying the wrong arguments/options. In thi...
Passing route control with optional parameter after root in express?
... Ernesto BadilloErnesto Badillo
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Rename Pandas DataFrame Index
...so here are some more examples:
In [1]: df = pd.DataFrame([[1, 2, 3], [4, 5 ,6]], columns=list('ABC'))
In [2]: df
Out[2]:
A B C
0 1 2 3
1 4 5 6
In [3]: df1 = df.set_index('A')
In [4]: df1
Out[4]:
B C
A
1 2 3
4 5 6
You can see the rename on the index, which can change...
Uninstall old versions of Ruby gems
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Steven Penny
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answered May 5 '11 at 18:33
Dylan MarkowDylan...
How do I create an empty array/matrix in NumPy?
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453
You have the wrong mental model for using NumPy efficiently. NumPy arrays are stored in contigu...
Convert varchar to uniqueidentifier in SQL Server
... I have no control of the schema for, contains a column defined as varchar(50) which stores uniqueidentifiers in the format 'a89b1acd95016ae6b9c8aabb07da2010' (no hyphens)
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