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How to perform .Max() on a property of all objects in a collection and return the object with maximu
...er which finds the maximum value on every iteration (making it O(n^2))
The ordering solution is O(n log n)
Taking the Max value and then finding the first element with that value is O(n), but iterates over the sequence twice. Where possible, you should use LINQ in a single-pass fashion.
It's a lot s...
PHP - Check if two arrays are equal
...$a === $b); // TRUE if $a and $b have the same key/value pairs in the same order and of the same types.
See Array Operators.
EDIT
The inequality operator is != while the non-identity operator is !== to match the equality
operator == and the identity operator ===.
...
What is the difference between Θ(n) and O(n)?
...ions aren't necessarily specific numbers, but instead functions of varying orders of magnitude such as log(n), n, n^2, (etc.).
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URL-parameters and logic in Django class-based views (TemplateView)
...
In case you pass URL parameter like this:
http://<my_url>/?order_by=created
You can access it in class based view by using self.request.GET (its not presented in self.args nor in self.kwargs):
class MyClassBasedView(ObjectList):
...
def get_queryset(self):
order_by...
SQL Server add auto increment primary key to existing table
... I would like to start counting at 1000. I suspect I can use ALTER TABLE ORDER ALTER COLUMN ORDERNO RESTART WITH 1 but I didn't want to try it without checking with an expert :) Ref. pic.dhe.ibm.com/infocenter/iseries/v7r1m0/…
– user1477388
Mar 8 '13 at 1...
How to normalize an array in NumPy?
...iving optimal performance.
import numpy as np
def normalized(a, axis=-1, order=2):
l2 = np.atleast_1d(np.linalg.norm(a, order, axis))
l2[l2==0] = 1
return a / np.expand_dims(l2, axis)
A = np.random.randn(3,3,3)
print(normalized(A,0))
print(normalized(A,1))
print(normalized(A,2))
prin...
Volatile vs. Interlocked vs. lock
...t multiple threads running on multiple CPUs can and will cache data and re-order instructions.
If it is not volatile, and CPU A increments a value, then CPU B may not actually see that incremented value until some time later, which may cause problems.
If it is volatile, this just ensures the two CPU...
How does HashSet compare elements for equality?
...y the default equality comparer.
Note how none of this is in terms of an ordered comparison - which makes sense, as there are certainly situations where you can easily specify equality but not a total ordering. This is all the same as Dictionary<TKey, TValue>, basically.
If you want a set w...
Select Row number in postgres
...
You should also specify an order in OVER clause: OVER (ORDER BY id). Otherwise the order is not guaranteed.
– AlexM
Jun 14 '16 at 4:30
...
generate days from date range
...ECT
date
FROM
dates
WHERE
date BETWEEN '2010-01-20' AND '2010-01-24'
ORDER BY
date
Update
It is worth noting that you will only be able to generate past dates starting from the current date. If you want to generate any kind of dates range (past, future, and in between), you will have to u...