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Changing column names of a data frame
...<- data.frame(bad=1:3, worse=rnorm(3))
R> X
bad worse
1 1 -2.440467
2 2 1.320113
3 3 -0.306639
R> colnames(X) <- c("good", "better")
R> X
good better
1 1 -2.440467
2 2 1.320113
3 3 -0.306639
You can also subset:
R> colnames(X)[2] <- "superduper"
...
How do you pass multiple enum values in C#?
...ple:
[Flags]
enum DaysOfWeek
{
Sunday = 1,
Monday = 2,
Tuesday = 4,
Wednesday = 8,
Thursday = 16,
Friday = 32,
Saturday = 64
}
public void RunOnDays(DaysOfWeek days)
{
bool isTuesdaySet = (days & DaysOfWeek.Tuesday) == DaysOfWeek.Tuesday;
if (isTuesdaySet)
//....
What happens when a computer program runs?
...
4 Answers
4
Active
...
How to delete multiple files at once in Bash on Linux?
... would be handled by brace expansion, like so:
$ rm -rf abc.log.2012-03-{14,27,28}
The above would expand to a single command with all three arguments, and be equivalent to typing:
$ rm -rf abc.log.2012-03-14 abc.log.2012-03-27 abc.log.2012-03-28
It's important to note that this expansion is d...
What key shortcuts are to comment and uncomment code?
...|
edited Mar 20 '13 at 13:49
Soner Gönül
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...
Printing everything except the first field with awk
...
4
and a extra trailing space
– NeronLeVelu
Aug 6 '15 at 7:37
...
What are the default access modifiers in C#?
...
498
The default access for everything in C# is "the most restricted access you could declare for t...
How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...:string test = "0123123";
size_t match1 = test.rfind("123"); // returns 4 (rightmost match)
size_t match2 = test.rfind("123", 2); // returns 1 (skipped over later match)
size_t match3 = test.rfind("123", 0); // returns std::string::npos (i.e. not found)
...
How do you copy the contents of an array to a std::vector in C++ without looping?
... |
edited Mar 10 '17 at 14:54
phoenix
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answered N...
How can I update npm on Windows?
...edited Aug 18 '17 at 18:56
user34612
10911 silver badge44 bronze badges
answered Jul 20 '15 at 15:37
Robert Ba...