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When to use Cast() and Oftype() in Linq
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answered Oct 25 '10 at 15:13
Itay KaroItay Karo
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In PHP, how do you change the key of an array element?
... want to check for it.
– Peeech
Mar 10 '13 at 12:19
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show 8 more comments
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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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Avoid duplicates in INSERT INTO SELECT query in SQL Server
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nloewen
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answered Mar 25 '10 at 5:07
OMG PoniesOMG Ponies
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How do I get the first n characters of a string without checking the size or going out of bounds?
... CStephen C
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1
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Why does int num = Integer.getInteger(“123”) throw NullPointerException?
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answered Jun 26 '10 at 9:18
polygenelubricantspolygenelubricants
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Passing command line arguments in Visual Studio 2010?
... how to pass command line arguments to my main function in Visual Studio 2010 Express Edition. I want to debug - how do these command line arguments work?
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How do I make class methods / properties in Swift?
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answered May 11 '15 at 10:49
techloverrtechloverr
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Plot smooth line with PyPlot
...t; from scipy.interpolate import interp1d
>>> x = np.linspace(0, 10, num=11, endpoint=True)
>>> y = np.cos(-x**2/9.0)
>>> f = interp1d(x, y)
>>> f2 = interp1d(x, y, kind='cubic')
>>> xnew = np.linspace(0, 10, num=41, endpoint=True)
>>> import m...
Formatting a float to 2 decimal places
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answered Jun 15 '11 at 10:34
WraithNathWraithNath
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