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Drop all duplicate rows across multiple columns in Python Pandas
...ates and the keep parameter.
import pandas as pd
df = pd.DataFrame({"A":["foo", "foo", "foo", "bar"], "B":[0,1,1,1], "C":["A","A","B","A"]})
df.drop_duplicates(subset=['A', 'C'], keep=False)
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What is the instanceof operator in JavaScript?
...al inheritance.
For example, let's define a type and a subtype:
function Foo(){ //a Foo constructor
//assign some props
return this;
}
function SubFoo(){ //a SubFoo constructor
Foo.call( this ); //inherit static props
//assign some new props
return this;
}
SubFoo.prototype = ...
Why don't C++ compilers define operator== and operator!=?
... Viktor, I suggest you re-think your response. If the class Foo contains a Bar*, then how would the compiler know whether Foo::operator== wants to compare the address of Bar*, or the contents of Bar?
– Mark Ingram
Sep 1 '10 at 13:59
...
What do the parentheses around a function name mean?
...
In the absence of any preprocessor stuff going on, foo's signature is equivalent to
int foo (int *bar)
The only context in which I've seen people putting seemingly unnecessary parentheses around function names is when there are both a function and a function-like macro wit...
How do I implement IEnumerable
...>'s GetEnumerator in the explicit implementation of IEnumerable:
class FooCollection : IEnumerable<Foo>, IEnumerable
{
SomeCollection<Foo> foos;
// Explicit for IEnumerable because weakly typed collections are Bad
System.Collections.IEnumerator IEnumerable.GetEnumerator(...
Javascript “this” pointer within nested function
...on , try to get the output for the following snippet
var myObject = {
foo: "bar",
func: function() {
var self = this;
console.log("outer func: this.foo = " + this.foo);
console.log("outer func: self.foo = " + self.foo);
(function() {
console.log...
difference between variables inside and outside of __init__()
...
Without Self
Create some objects:
class foo(object):
x = 'original class'
c1, c2 = foo(), foo()
I can change the c1 instance, and it will not affect the c2 instance:
c1.x = 'changed instance'
c2.x
>>> 'original class'
But if I change the foo clas...
Inherit docstrings in Python class inheritance
... was created. Check it out here.
"""
doc_inherit decorator
Usage:
class Foo(object):
def foo(self):
"Frobber"
pass
class Bar(Foo):
@doc_inherit
def foo(self):
pass
Now, Bar.foo.__doc__ == Bar().foo.__doc__ == Foo.foo.__doc__ == "Frobber"
"""
from functools ...
Swift: Convert enum value to String?
...e interface and access the description getter. Define your enum as:
enum Foo : CustomStringConvertible {
case Bing
case Bang
case Boom
var description : String {
switch self {
// Use Internationalization, as appropriate.
case .Bing: return "Bing"
case .Bang: return "Ban...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
... assignment.
Consider the case of data extraction on the following list:
foo <- list( str='R', vec=c(1,2,3), bool=TRUE )
Say we would like to extract the value stored by bool from foo and use it inside an if() statement. This will illustrate the differences between the return values of [] and...