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Extracting specific columns from a data frame
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Using the dplyr package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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Find the min/max element of an Array in JavaScript
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Mr. Llama
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answered Nov 3 '09 at 18:23
Roatin MarthRoatin Ma...
How to check if a table contains an element in Lua?
Is there a method for checking if a table contains a value ? I have my own (naive) function, but I was wondering if something "official" exists for that ? Or something more efficient...
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Most useful NLog configurations [closed]
...than strictly configuration suggestions.
Here are some general logging links from here at SO (you might have seen some or all of these already):
log4net vs. Nlog
Logging best practices
What's the point of a logging facade?
Why do loggers recommend using a logger per class?
Use the common patte...
How do I set the path to a DLL file in Visual Studio?
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Go to project properties (Alt+F7)
Under Debugging, look to the right
There's an Environment field.
Add your relative path there (relative to vcproj folder) i.e. ..\some-framework\lib by appending PATH=%PATH%;$(ProjectDir)\some-framework\lib or prepending to the path PATH=C:\some...
How to reset AUTO_INCREMENT in MySQL?
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NielsNiels
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NULL values inside NOT IN clause
...t;> 2 and 3 <> null
When ansi_nulls is on, 3 <> null is UNKNOWN, so the predicate evaluates to UNKNOWN, and you don't get any rows.
When ansi_nulls is off, 3 <> null is true, so the predicate evaluates to true, and you get a row.
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Inserting a tab character into text using C#
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SteveC
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answered Dec 14 '08 at 3:25
DShookDShook
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What is a covariant return type?
...od which holds an explicit reference to a MyFoo object will be able to invoke clone() and know (without casting) that the return value is an instance of MyFoo. Without covariant return types, the overridden method in MyFoo would have to be declared to return Object - and so calling code would have ...
Remove stubborn underline from link
I am attempting to have a link show up in white, without an underline. The text color shows up correctly as white, but the blue underline is stubbornly persisting. I tried text-decoration: none; and text-decoration: none !important; in the CSS to remove the link underline. Neither worked.
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