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How to index into a dictionary?
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Dictionaries are unordered in Python versions up to and including Python 3.6. If you do not care about the order of the entries and want to access the keys or values by index anyway, you can use d.keys()[i] and d.values()[i] or d.items()[i]. ...
Is python's sorted() function guaranteed to be stable?
..., 1), (1, 2)] instead of returning the original input in the same sequence/order. Shouldn't the guarantee of stability mean that it should be returning the original [(1, 2), (1, 1)] input? In that case, you have be explicit and say sorted([(1, 2), (1, 1)], key=lambda t: t[0])
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Python list subtraction operation
... x - y
But if you don't absolutely need list properties (for example, ordering), just use sets as the other answers recommend.
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Undefined behavior and sequence points
...haviour and Implementation Defined Behaviour.
You must also know that the order of evaluation of operands of individual operators and subexpressions of individual expressions, and the order in which side effects take place, is unspecified.
For example:
int x = 5, y = 6;
int z = x++ + y++; //it i...
How to efficiently compare two unordered lists (not sets) in Python?
...ered equal, because they have exactly the same elements, only in different order.
10 Answers
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“Order by Col1, Col2” using entity framework
I need to order by 2 columns using the entity framework.
5 Answers
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Difference between clustered and nonclustered index [duplicate]
...mn(s). It is like a dictionary, where all words are sorted in alphabetical order in the entire book.
A non-clustered index, on the other hand, does not alter the way the rows are stored in the table. It creates a completely different object within the table that contains the column(s) selected for...
How to use orderby with 2 fields in linq? [duplicate]
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MyList.OrderBy(x => x.StartDate).ThenByDescending(x => x.EndDate);
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LINQ to SQL Left Outer Join
..., for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
select new {
CustomerID = c.CustomerID, ContactName = c.ContactName,
OrderI...
SQL - using alias in Group By
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SQL is implemented as if a query was executed in the following order:
FROM clause
WHERE clause
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause
For most relational database systems, this order explains which names (columns or aliases) are valid because they must have been ...