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Replacing column values in a pandas DataFrame
...e this:
w['female'] = w['female'].map({'female': 1, 'male': 0})
(Here I convert the values to numbers instead of strings containing numbers. You can convert them to "1" and "0", if you really want, but I'm not sure why you'd want that.)
The reason your code doesn't work is because using ['femal...
LINQ Aggregate algorithm explained
...regate is that it performs an operation on each element of the list taking into account the operations that have gone before. That is to say it performs the action on the first and second element and carries the result forward. Then it operates on the previous result and the third element and carrie...
C++11 reverse range-based for-loop
...nclude <iostream>
#include <boost/range/adaptor/reversed.hpp>
int main()
{
std::list<int> x { 2, 3, 5, 7, 11, 13, 17, 19 };
for (auto i : boost::adaptors::reverse(x))
std::cout << i << '\n';
for (auto i : x)
std::cout << i << '\n...
When to use extern in C++
I'm reading "Think in C++" and it just introduced the extern declaration. For example:
4 Answers
...
Comparing two collections for equality irrespective of the order of items in them
... comparer. It is more complete than existing answers, since it takes nulls into account, implements IEqualityComparer and has some efficiency and edge case checks. plus, it's Microsoft :)
public class MultiSetComparer<T> : IEqualityComparer<IEnumerable<T>>
{
private readonly I...
Link to add to Google calendar
...
To convert to the datetime format: (new Date()).toISOString().replace(/-|:|\.\d\d\d/g,"");
– Trantor Liu
Dec 30 '14 at 10:36
...
How to define “type disjunction” (union types)?
...declare a class with the types you wish to accept as below:
class StringOrInt[T]
object StringOrInt {
implicit object IntWitness extends StringOrInt[Int]
implicit object StringWitness extends StringOrInt[String]
}
Next, declare foo like this:
object Bar {
def foo[T: StringOrInt](x: T) = x ...
How to get screen dimensions as pixels in Android
... use getSize:
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int width = size.x;
int height = size.y;
If you're not in an Activity you can get the default Display via WINDOW_SERVICE:
WindowManager wm = (WindowManager) context.getSystemS...
How do I return multiple values from a function in C?
If I have a function that produces a result int and a result string , how do I return them both from a function?
8 Answe...
Default value to a parameter while passing by reference in C++
... way round this would be to use an actual instance as the default:
static int AVAL = 1;
void f( int & x = AVAL ) {
// stuff
}
int main() {
f(); // equivalent to f(AVAL);
}
but this is of very limited practical use.
...