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Mongoose subdocuments vs nested schema
...still have the same subdocument structure.
– Martin Hallén
Jul 9 '14 at 9:17
2
you should also c...
What does %w(array) mean?
....], curly braces %w{...} or even something like exclamation marks %w!...!. All of these have the same behavior (returning an array).
– ryanb
Aug 13 '09 at 21:40
146
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Read entire file in Scala?
...simple and canonical way to read an entire file into memory in Scala? (Ideally, with control over character encoding.)
18 ...
What is the best algorithm for overriding GetHashCode?
...hroughout the .NET base class libraries. Implementing it properly is especially important to find items quickly in a collection or when determining equality.
...
not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
What does the “at” (@) symbol do in Python?
...
Example
class Pizza(object):
def __init__(self):
self.toppings = []
def __call__(self, topping):
# When using '@instance_of_pizza' before a function definition
# the function gets passed onto 'topping'.
self.toppings.appe...
Schema for a multilanguage database
...izability is not an issue. We can use language specific resources and have all kinds of tools that work well with them.
12 ...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
...