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Clojure 1.2.1/1.3/1.4 'proxy generated in Grails 2.0.0 runtime fails. 1.2.0 is fine
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4
I found an Issue called CLJ-944 on clojure.org. There you can find a fix for ClassCastException:...
What's the 'Ruby way' to iterate over two arrays at once
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Marc-André Lafortune
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answered Aug 26 '10 at 22:31
John La RooyJohn...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
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4 Answers
4
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How to drop columns by name in a data frame
... function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2
2 2 3
3 3 4...
Does the ternary operator exist in R?
...(x)]])
here, you don't need to take care about brackets:
> 1 ? 2*3 : 4
[1] 6
> 0 ? 2*3 : 4
[1] 4
> TRUE ? x*2 : 0
[1] 2
> FALSE ? x*2 : 0
[1] 0
but you need brackets for assignment :(
> y <- 1 ? 2*3 : 4
[1] 6
> y
[1] 1
> y <- (1 ? 2*3 : 4)
> y
[1] 6
Finally, y...
Regex to match a digit two or four times
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145
There's no specific syntax for that, but there are lots of ways to do it:
(?:\d{4}|\d{2}) &...
Is there an easy way to check the .NET Framework version?
... like this should do it. Just grab the value from the registry
For .NET 1-4:
Framework is the highest installed version, SP is the service pack for that version.
RegistryKey installed_versions = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
string[] version_name...
Grep regex NOT containing string
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beerbajaybeerbajay
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Apache: “AuthType not set!” 500 Error
...he line that says
Require all granted
it's only needed on Apache >=2.4
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Convert numpy array to tuple
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edited Jul 18 '13 at 22:34
answered Apr 4 '12 at 17:35
Nik...