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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 :
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Do you need break in switch when return is used?
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NanneNanne
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Asynchronous Process inside a javascript for loop [duplicate]
...(i);
});
});
Create Your Own Function Closure Using an IIFE
var j = 10;
for (var i = 0; i < j; i++) {
(function(cntr) {
// here the value of i was passed into as the argument cntr
// and will be captured in this function closure so each
// iteration of the loop ...
Is ASCII code 7-bit or 8-bit?
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zwolzwol
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How to normalize an array in NumPy?
...umpy as np
from sklearn.preprocessing import normalize
x = np.random.rand(1000)*10
norm1 = x / np.linalg.norm(x)
norm2 = normalize(x[:,np.newaxis], axis=0).ravel()
print np.all(norm1 == norm2)
# True
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How to publish a website made by Node.js to Github Pages?
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104
GitHub pages host only static HTML pages. No server side technology is supported, so Node.js a...
When is a Java method name too long? [closed]
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answered Feb 9 '10 at 17:01
JaredParJaredPar
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How are the points in CSS specificity calculated
...important)
So there is, effectively, a "point system," but it's not base 10. It's base 256. Here's how it works:
(28)2 or 65536, times the number of ids in the selector
+ (28)1 or 256, times the number of class-names in the selector
+ (28)0 or 1, times the number of tag-names in the selector
Th...
Why am I suddenly getting a “Blocked loading mixed active content” issue in Firefox?
...of the protocol):
<link rel="stylesheet" href="//code.jquery.com/ui/1.8.10/themes/smoothness/jquery-ui.css" type="text/css">
<script type="text/javascript" src="//ajax.aspnetcdn.com/ajax/jquery.ui/1.8.10/jquery-ui.min.js"></script>
Note that the temporary 'fix' is to click on the ...
How to negate the whole regex?
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102
Use negative lookaround: (?!pattern)
Positive lookarounds can be used to assert that a patter...