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Determine the data types of a data frame's columns
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220
Your best bet to start is to use ?str(). To explore some examples, let's make some data:
s...
Get top n records for each group of grouped results
... select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this article to determine the best route for your situation:
http://www.xaprb.com/b...
How exactly does tail recursion work?
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answered Mar 20 '13 at 9:11
Alexey FrunzeAlexey Frunze
56.8k99 gold badges6767 silver badges154154 bronze badges
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How to delete duplicate rows in SQL Server?
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23 Answers
23
Active
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What is the Difference Between read() and recv() , and Between send() and write()?
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edited Jul 25 '19 at 9:07
smbear
92299 silver badges1515 bronze badges
answered Nov 24 '0...
Is there a way to list pip dependencies/requirements?
...o I am providing an updated answer.
This was tested with pip versions 8.1.2, 9.0.1, 10.0.1, and 18.1.
To get the output without cluttering your current directory on Linux use
pip download [package] -d /tmp --no-binary :all: -v
-d tells pip the directory that download should put files in.
Bette...
Python integer division yields float
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292
Take a look at PEP-238: Changing the Division Operator
The // operator will be available t...
How do I exchange keys with values in a dictionary?
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Python 2:
res = dict((v,k) for k,v in a.iteritems())
Python 3 (thanks to @erik):
res = dict((v,k) for k,v in a.items())
share
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Passing parameters to a Bash function
...and...
}
To call a function with arguments:
function_name "$arg1" "$arg2"
The function refers to passed arguments by their position (not by name), that is $1, $2, and so forth. $0 is the name of the script itself.
Example:
function_name () {
echo "Parameter #1 is $1"
}
Also, you need to...
Changing Vim indentation behavior by file type
...the file type? For instance, if I open a Python file it should indent with 2 spaces, but if I open a Powershell script it should use 4 spaces.
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