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Why is using “for…in” for array iteration a bad idea?
...5; // Perfectly legal JavaScript that resizes the array.
for (var i = 0; i < a.length; i++) {
// Iterate over numeric indexes from 0 to 5, as everyone expects.
console.log(a[i]);
}
/* Will display:
undefined
undefined
undefined
undefined
undefined
5
*/
...
Sort array of objects by single key with date value
... use Array.sort.
Here's an example:
var arr = [{
"updated_at": "2012-01-01T06:25:24Z",
"foo": "bar"
},
{
"updated_at": "2012-01-09T11:25:13Z",
"foo": "bar"
},
{
"updated_at": "2012-01-05T04:13:24Z",
"foo": "bar"
}
]
arr.sort(function(a, b) {
v...
How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...
Getting LaTeX into R Plots
...
answered Sep 12 '09 at 1:11
Christopher DuBoisChristopher DuBois
36.7k2323 gold badges6565 silver badges9191 bronze badges
...
Transposing a 2D-array in JavaScript
...
210
array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided ...
Is there a JavaScript strcmp()?
...
answered Jul 24 '09 at 18:38
newacctnewacct
106k2626 gold badges143143 silver badges214214 bronze badges
...
Check if an element is present in an array [duplicate]
...
1044
ECMAScript 2016 incorporates an includes() method for arrays that specifically solves the prob...
Efficiently test if a port is open on Linux?
...o use:
exec 6<>/dev/tcp/ip.addr.of.server/445
echo -e "GET / HTTP/1.0\n" >&6
cat <&6
I'm using 6 as the file descriptor because 0,1,2 are stdin, stdout, and stderr. 5 is sometimes used by Bash for child processes, so 3,4,6,7,8, and 9 should be safe.
As per the comment below, ...
Regular expression for a hexadecimal number?
...
How about the following?
0[xX][0-9a-fA-F]+
Matches expression starting with a 0, following by either a lower or uppercase x, followed by one or more characters in the ranges 0-9, or a-f, or A-F
...
Change URL parameters
...ed Sujoy's code to make up a function.
/**
* http://stackoverflow.com/a/10997390/11236
*/
function updateURLParameter(url, param, paramVal){
var newAdditionalURL = "";
var tempArray = url.split("?");
var baseURL = tempArray[0];
var additionalURL = tempArray[1];
var temp = "";
...