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How to get row from R data.frame
...for example:
#Add your data
x <- structure(list(A = c(5, 3.5, 3.25, 4.25, 1.5 ),
B = c(4.25, 4, 4, 4.5, 4.5 ),
C = c(4.5, 2.5, 4, 2.25, 3 )
),
.Names = c("A", "B", "C"),
class = "data.f...
Concatenating two one-dimensional NumPy arrays
... explicit sequences).
– Jim K.
Aug 24 '16 at 20:43
@JimK. What would happen to the axis parameter?
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What is the best regular expression to check if a string is a valid URL?
...
415
I wrote my URL (actually IRI, internationalized) pattern to comply with RFC 3987 (http://www.f...
Filter rows which contain a certain string
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4 Answers
4
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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...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
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14 Answers
14
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What is the ultimate postal code and zip regex?
...le IMO. But you would still be missing on the validation part: Zip code 12345 may exist, but 12346 not, maybe 12344 doesn't exist either. How do you check for that with a regex?
You can't.
share
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Can dplyr package be used for conditional mutating?
...f %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; howev...
Why does “,,,” == Array(4) in Javascript?
...d operand is converted to a string and the string representation of Array(4) is ,,,:
> Array(4).toString()
",,,"
If you use the array constructor function and pass a number, it sets the length of the array to that number. So you can say you have four empty indexes (same as [,,,]) and the de...