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Drop data frame columns by name
...d like to remove from a data frame. I know that we can delete them individually using something like:
20 Answers
...
PHP function overloading
...um_args() and func_get_arg() to get the arguments passed, and use them normally.
For example:
function myFunc() {
for ($i = 0; $i < func_num_args(); $i++) {
printf("Argument %d: %s\n", $i, func_get_arg($i));
}
}
/*
Argument 0: a
Argument 1: 2
Argument 2: 3.5
*/
myFunc('a', 2, 3...
Knight's Shortest Path on Chessboard
...
You have a graph here, where all available moves are connected (value=1), and unavailable moves are disconnected (value=0), the sparse matrix would be like:
(a1,b3)=1,
(a1,c2)=1,
.....
And the shortest path of two points in a graph can be found usin...
How do I use IValidatableObject?
... Prop1 = 1,
Prop2 = 2
};
bool validateAllProperties = false;
var results = new List<ValidationResult>();
bool isValid = Validator.TryValidateObject(
toValidate,
new ValidationContext(toValidate, null, null),
...
Is it possible to implement a Python for range loop without an iterator variable?
...ou can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last result that returned in an interactive python session:
>>> 1+2
3
>>> _
3
F...
What differences, if any, between C++03 and C++11 can be detected at run-time?
...onstrate breaking changes. The following is a tweaked testcase, which initially was used to demonstrate such a change, but now is used to test for C++0x or C++03.
struct X { };
struct Y { X x1, x2; };
struct A { static X B(int); };
typedef A B;
struct C : A {
using ::B::B; // (inheriting const...
Is it possible to declare two variables of different types in a for loop?
...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set to 1.0
std::string s set to "...
Find which version of package is installed with pip
..., is it possible to figure out which version of a package is currently installed?
15 Answers
...
Refused to display in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'
...ight='760' src="https://www.youtube.com/embed/dQw4w9WgXcQ" frameborder="0" allowfullscreen></iframe>
– backwardm
Aug 5 '15 at 20:28
2
...
Why would a JavaScript variable start with a dollar sign? [duplicate]
...wish the jquery documentation used this notation as well... It is indeed really helpful.
– pedromanoel
Jan 28 '14 at 11:05
10
...