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Javascript - sort array based on another array
...he sorting array:
result = items.map(function(item) {
var n = sorting.indexOf(item[1]);
sorting[n] = '';
return [n, item]
}).sort().map(function(j) { return j[1] })
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Strings as Primary Keys in SQL Database [closed]
... wouldn't it depend on the database? I would think a properly indexed string would not be that much slower if at all from a number?
– Ryan Guill
Feb 5 '09 at 20:09
2
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How do I delete rows in a data frame?
...ven by the '-' operator" -> This is a very misleading wording. Negative indexes are removed and that's it, there is no notion of complement. If you work with logical and try using - it won't work, because the complement operator for logicals is !. The complement of c(2,4,6) in the rows would rath...
How can one see the structure of a table in SQLite? [duplicate]
...sqlite3.
Example:
sqlite> entropy:~/Library/Mail>sqlite3 Envelope\ Index
SQLite version 3.6.12
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> .tables
addresses ews_folders subjects
alarms feeds thr...
How to get first 5 characters from string [duplicate]
... use this, but for the purpose of education. We can use that to answer the question:
$newString = '';
for ($i = 0; $i < 5; $i++) {
$newString .= $str{$i};
}
echo $newString;
For anyone using that. Bear in mind curly brace syntax for accessing array elements and string offsets is deprecated f...
cartesian product in pandas
...
Use pd.MultiIndex.from_product as an index in an otherwise empty dataframe, then reset its index, and you're done.
a = [1, 2, 3]
b = ["a", "b", "c"]
index = pd.MultiIndex.from_product([a, b], names = ["a", "b"])
pd.DataFrame(index = ...
GIT: Checkout to a specific folder
...
As per Do a "git export" (like "svn export")?
You can use git checkout-index for that, this is a low level command, if you want to export everything, you can use -a,
git checkout-index -a -f --prefix=/destination/path/
To quote the man pages:
The final "/" [on the prefix] is important. Th...
How can I get the corresponding table header (th) from a table cell (td)?
... $th = $td.closest('tbody').prev('thead').find('> tr > th:eq(' + $td.index() + ')');
Or a little bit simplified
var $th = $td.closest('table').find('th').eq($td.index());
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How to enable cURL in PHP / XAMPP
...>____ to switch to those versions, as described here: stackoverflow.com/q/10939248/79444
– veljkoz
Aug 24 '12 at 17:33
...
Flatten an Array of Arrays in Swift
...ay.flatten(0, self)
}
public static func flatten<Element>(_ index: Int, _ toFlat: [Element]) -> [Element] {
guard index < toFlat.count else { return [] }
var flatten: [Element] = []
if let itemArr = toFlat[index] as? [Element] {
flatten = fl...