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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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What is the difference between “INNER JOIN” and “OUTER JOIN”?
Also how do LEFT JOIN , RIGHT JOIN and FULL JOIN fit in?
27 Answers
27
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Capturing Groups From a Grep RegEx
..._[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
echo "$f doesn't...
Find the host name and port using PSQL commands
I have PSQL running, and am trying to get a perl application connecting to the database. Is there a command to find the current port and host that the database is running on?
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Create a string of variable length, filled with a repeated character
...Java form here: Java - Create a new String instance with specified length and filled with specific character. Best solution?
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What does the “at” (@) symbol do in Python?
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An @ symbol at the beginning of a line is used for class, function and method decorators.
Read more here:
PEP 318: Decorators
Python Decorators
The most common Python decorators you'll run into are:
@property
@classmethod
@staticmethod
If you see an @ in the middle of a line, that's ...
Conversion of a datetime2 data type to a datetime data type results out-of-range value
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I changed my datacolumns and used typeof now... Further I found my problem. there was 1 datarow that contained a wrong date, which triggered the error
– Gerbrand
Aug 26 '09 at 5:46
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Resize HTML5 canvas to fit window
...get rid of the scrollbars, add "overflow: hidden" to the style of the html and body elements. See thefutureoftheweb.com/blog/100-percent-height-interface
– Denis Washington
Mar 16 '12 at 7:45
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How do I find the next commit in git? (child/children of ref)
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To list all the commits, starting from the current one, and then its child, and so on - basically standard git log, but going the other way in time, use something like
git log --reverse --ancestry-path 894e8b4e93d8f3^..master
where 894e8b4e93d8f3 is the first commit you want to...
Primary key/foreign Key naming convention [closed]
... group we have a raging debate regarding the naming convention for Primary and Foreign Keys. There's basically two schools of thought in our group:
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