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Java: how to convert HashMap to array
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Mayonnaise2124
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answered Jul 7 '09 at 5:47
Landon KuhnLandon Kuhn
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Drop data frame columns by name
...st 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 :
For those still not acquainted wi...
Get integer value from string in swift
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edited Sep 3 '15 at 11:50
answered Jun 12 '15 at 11:43
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Forward declaring an enum in C++
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KJAWolfKJAWolf
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Using Mockito with multiple calls to the same method with the same arguments
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answered Nov 11 '11 at 0:21
Igor NikolaevIgor Nikolaev
3,75711 gold badge1414 silver badges1919 bronze badges
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Return empty cell from formula in Excel
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J.T. GrimesJ.T. Grimes
4,00411 gold badge2525 silver badges3131 bronze badges
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gitignore without binary files
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VenomVendorVenomVendor
13.6k1111 gold badges6262 silver badges8888 bronze badges
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How to combine two or more querysets in a Django view?
... obj: obj.id)]
– Josh Russo
Sep 18 '11 at 22:21
2
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Remove trailing zeros
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edited May 23 '17 at 11:47
Community♦
111 silver badge
answered Dec 24 '10 at 11:14
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How to efficiently build a tree from a flat structure?
...ld post the sol for 0(1N)
– Ced
Aug 11 '15 at 15:57
1
@Ced Martin Schmidt's answer below is very ...