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What does enumerate() mean?
...gt; for count, elem in enumerate(elements):
... print count, elem
...
0 foo
1 bar
2 baz
By default, enumerate() starts counting at 0 but if you give it a second integer argument, it'll start from that number instead:
>>> for count, elem in enumerate(elements, 42):
... print coun...
How to prevent page scrolling when scrolling a DIV element?
...'.scrollable' ).on( 'mousewheel DOMMouseScroll', function ( e ) {
var e0 = e.originalEvent,
delta = e0.wheelDelta || -e0.detail;
this.scrollTop += ( delta < 0 ? 1 : -1 ) * 30;
e.preventDefault();
});
Live demo: https://jsbin.com/howojuq/edit?js,output
So you manually set t...
Printf width specifier to maintain precision of floating-point value
...n:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
Let...
How to read data from a zip file without having to unzip the entire file
...n zip)
{
if (header)
{
System.Console.WriteLine("Zipfile: {0}", zip.Name);
if ((zip.Comment != null) && (zip.Comment != ""))
System.Console.WriteLine("Comment: {0}", zip.Comment);
System.Console.WriteLine("\n{1,-22} {2,8} {3,5} {4,8} {5,3} {0}",
...
What's the difference between => , ()=>, and Unit=>
...s function:
def f(x: => Int) = x * x
If I call it like this
var y = 0
f { y += 1; y }
Then the code will execute like this
{ y += 1; y } * { y += 1; y }
Though that raises the point of what happens if there's a identifier name clash. In traditional call-by-name, a mechanism called captur...
std::function vs template
...
answered Feb 3 '13 at 22:50
Andy ProwlAndy Prowl
111k1818 gold badges348348 silver badges430430 bronze badges
...
Python to print out status bar and percentage
...t progressbar
from time import sleep
bar = progressbar.ProgressBar(maxval=20, \
widgets=[progressbar.Bar('=', '[', ']'), ' ', progressbar.Percentage()])
bar.start()
for i in xrange(20):
bar.update(i+1)
sleep(0.1)
bar.finish()
To install it, you can use easy_install progressbar, or pip ...
Append an object to a list in R in amortized constant time, O(1)?
...
R>
That works on vectors too, so do I get the bonus points?
Edit (2015-Feb-01): This post is coming up on its fifth birthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(ol...
delete map[key] in go?
...
coolaj86
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answered Nov 15 '09 at 1:22
user181548user...
Two statements next to curly brace in an equation
...cument}
\begin{equation}
f(x)=\begin{cases}
1, & \text{if $x<0$}.\\
0, & \text{otherwise}.
\end{cases}
\end{equation}
\end{document}
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