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Does python have a sorted list?
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edited Dec 7 '18 at 9:57
Arne
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answer...
Drop data frame columns by name
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You can use a simple list of names :
DF <- data.frame(
x=1:10,
y=10:1,
z=rep(5,10),
a=11:20
)
drops <- c("x","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT ...
How to check if a specified key exists in a given S3 bucket using Java
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16 Answers
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How to install trusted CA certificate on Android device?
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119
Prior to Android KitKat you have to root your device to install new certificates.
From Androi...
Best way to do multi-row insert in Oracle?
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173
This works in Oracle:
insert into pager (PAG_ID,PAG_PARENT,PAG_NAME,PAG_ACTIVE)
sel...
How can I use a file in a command and redirect output to the same file without truncating it?
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14 Answers
14
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ASP.NET MS11-100: how can I change the limit on the maximum number of posted form values?
Microsoft recently (12-29-2011) released an update to address several serious security vulnerabilities in the .NET Framework. One of the fixes introduced by MS11-100 temporarily mitigates a potential DoS attack involving hash table collisions. It appears this fix breaks pages that contain a lot ...
How to generate Class Diagram (UML) on Android Studio (IntelliJ Idea)
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110
I found a free plugin that can generate class diagrams with android studio.
It's called Simple...