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Order data frame rows according to vector with specific order
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Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target <- c("b", "c", "a", "d")
df[match(target, df$name),]
name value
2 b TRUE
3 c FALSE
1 a TRUE
4 d FALSE
It will work as long as your target contains exact...
How to read the mode field of git-ls-tree's output
...The following flags are defined for the st_mode field:
S_IFMT 0170000 bit mask for the file type bit fields
S_IFSOCK 0140000 socket
S_IFLNK 0120000 symbolic link
S_IFREG 0100000 regular file
S_IFBLK 0060000 block device
S_IFDIR 0...
string.Format() giving “Input string is not in correct format”
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What is the lifetime of a static variable in a C++ function?
...ects must run in the reverse order of the completion of their construction[1], and the order of construction may depend on the specific program run, the order of construction must be taken into account.
Example
struct emitter {
string str;
emitter(const string& s) : str(s) { cout <<...
Is there a REAL performance difference between INT and VARCHAR primary keys?
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Bypass confirmation prompt for pip uninstall
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starting with pip version 7.1.2 you can run pip uninstall -y <python package(s)>
pip un...
When to use std::forward to forward arguments?
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Use it like your first example:
template <typename T> void f(T && x)
{
g(std:...
Scroll back to the top of scrollable div
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