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Clang vs GCC - which produces faster binaries? [closed]
...lity) of binaries it produces - if gcc -O3 can produce a binary that runs 1% faster, or Clang binaries take up more memory or just fail due to compiler bugs, it's a deal-breaker.
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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 ...
What MySQL data type should be used for Latitude/Longitude with 8 decimal places?
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610
DECIMAL is the MySQL data-type for exact arithmetic. Unlike FLOAT its precision is fixed for an...
Swift equivalent for MIN and MAX macros
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125
min and max are already defined in Swift:
func max<T : Comparable>(x: T, y: T, rest: T....
Where in an Eclipse workspace is the list of projects stored?
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153
Windows:
<workspace>\.metadata\.plugins\org.eclipse.core.resources\.projects\
Linux /...
Scala: Nil vs List()
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189
scala> println (Nil == List())
true
scala> println (Nil eq List())
true
scala> prin...
Most efficient way to make the first character of a String lower case?
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11 Answers
11
Active
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How to get a list of properties with a given attribute?
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answered Feb 17 '10 at 16:09
Marc Gravell♦Marc Gravell
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Can I use the range operator with if statement in Swift?
...hree assembly instruction:
addq $-200, %rdi
cmpq $99, %rdi
ja LBB0_1
this is exactly the same assembly code that is generated for
if statusCode >= 200 && statusCode <= 299
You can verify that with
xcrun -sdk macosx swiftc -O -emit-assembly main.swift
As of Swift 2, thi...
Virtualbox “port forward” from Guest to Host [closed]
...t and find out the ip address:
ifconfig
example of result (ip address is 10.0.2.15):
eth0 Link encap:Ethernet HWaddr 08:00:27:AE:36:99
inet addr:10.0.2.15 Bcast:10.0.2.255 Mask:255.255.255.0
Go to Vbox instance window -> Menu -> Network adapters:
adapter should be NAT
cli...