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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...
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());
share
|
improve t...
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...
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SQL Server SELECT LAST N Rows
...hout a sort of some nature this simply won't work, the best solution is to index the major columns being hit and run with something like the above query.
– JonVD
Nov 16 '10 at 23:15
...
Comparing two dataframes and getting the differences
...dentical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, one approach might be concatenate datafr...
Count Rows in Doctrine QueryBuilder
...lass);
$count = $repository->count();
And in Repository/FooRepository.php
public function count()
{
$qb = $repository->createQueryBuilder('t');
return $qb
->select('count(t.id)')
->getQuery()
->getSingleScalarResult();
}
It's better to move $qb = ....
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