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Replacement for “rename” in dplyr
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dplyr version 0.3 added a new rename() function that works just like plyr::rename().
df <- rename(df, new_name = old_name)
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How to get last items of a list in Python?
...re's an example using the python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
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CSS Selector that applies to elements with two classes
...attribute being set to two specific classes. For example, let's say I have 3 divs:
1 Answer
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How would I get a cron job to run every 30 minutes?
I'm looking to add a crontab entry to execute a script every 30 minutes, on the hour and 30 minutes past the hour or something close. I have the following, but it doesn't seem to run on 0.
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In Vim, how do I apply a macro to a set of lines?
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368
Use the normal command in Ex mode to execute the macro on multiple/all lines:
Execute the mac...
c# datatable insert column at position 0
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3 Answers
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To find whether a column exists in data frame or not
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answered Apr 23 '12 at 7:03
user554546user554546
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Django: Set foreign key using integer?
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answered May 17 '10 at 3:44
Will HardyWill Hardy
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How do I write data into CSV format as string (not file)?
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edited Jan 13 '17 at 21:13
TH22
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How to move columns in a MySQL table?
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351
If empName is a VARCHAR(50) column:
ALTER TABLE Employees MODIFY COLUMN empName VARCHAR(50) A...