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Passing an integer by reference in Python
...nd is to pass the integer in a container which can be mutated:
def change(m>x m>):
m>x m>[0] = 3
m>x m> = [1]
change(m>x m>)
print m>x m>
This is ugly/clumsy at best, but you're not going to do any better in Python. The reason is because in Python, assignment (=) takes whatever object is the result of the right hand...
How to remove ASP.Net MVC Default HTTP Headers?
...
m>X m>-Powered-By is a custom header in IIS. Since IIS 7, you can remove it by adding the following to your web.config:
<system.webServer>
<httpProtocol>
<customHeaders>
<remove name="m>X m>-Powered-By...
Understanding the map function
...omprehensions instead:
map(f, iterable)
is basically equivalent to:
[f(m>x m>) for m>x m> in iterable]
map on its own can't do a Cartesian product, because the length of its output list is always the same as its input list. You can trivially do a Cartesian product with a list comprehension though:
[(a,...
Why are regular em>x m>pressions so controversial? [closed]
When em>x m>ploring regular em>x m>pressions (otherwise known as RegEm>x m>-es), there are many individuals who seem to see regular em>x m>pressions as the Holy Grail. Something that looks so complicated - just must be the answer to any question. They tend to think that every problem is solvable using regular em>x m>press...
Best practices for circular shift (rotate) operations in C++
...otate question with some more details about what asm gcc/clang produce for m>x m>86.
The most compiler-friendly way to em>x m>press a rotate in C and C++ that avoids any Undefined Behaviour seems to be John Regehr's implementation. I've adapted it to rotate by the width of the type (using fim>x m>ed-width types ...
javascript set a variable if undefined
...f the variable is strictly undefined then the safest way is to write:
var m>x m> = (typeof m>x m> === 'undefined') ? your_default_value : m>x m>;
On newer browsers it's actually safe to write:
var m>x m> = (m>x m> === undefined) ? your_default_value : m>x m>;
but be aware that it is possible to subvert this on older browse...
Convert Int to String in Swift
...
Converting Int to String:
let m>x m> : Int = 42
var myString = String(m>x m>)
And the other way around - converting String to Int:
let myString : String = "42"
let m>x m>: Int? = myString.toInt()
if (m>x m> != nil) {
// Successfully converted String to Int
}
Or if ...
Python: split a list based on a condition?
...
1
2
Nem>x m>t
113
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In php, is 0 treated as empty?
Code will em>x m>plain more:
18 Answers
18
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Drop data frame columns by name
...
You can use a simple list of names :
DF <- data.frame(
m>x m>=1:10,
y=10:1,
z=rep(5,10),
a=11:20
)
drops <- c("m>x m>","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDI...