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Why is pow(a, d, n) so much faster than a**d % n?
...was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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How to create a new database after initally installing oracle database 11g Express Edition?
I have installed Oracle Database 11g Express Edition on my pc (windows 7)
and I have installed Oracle SQL Developer as well.
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How to detect that animation has ended on UITableView beginUpdates/endUpdates?
...ates . I am also using beginUpdates/endUpdates when adjusting rowHeight. All these operations are animated by default.
7 ...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
How to create has_and_belongs_to_many associations in Factory girl
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Thank you, most neat of all solutions.
– Mik
May 29 '12 at 19:14
Th...
Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
When maven says “resolution will not be reattempted until the update interval of MyRepo has elapsed”
With maven, I occasionally hit an artifact that comes from some 3rd-party repo that I haven't built or included in my repository yet.
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What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
Getting error: Peer authentication failed for user “postgres”, when trying to get pgsql working with
....conf file (/etc/postgresql/9.1/main/pg_hba.conf*).
This line:
local all postgres peer
Should be:
local all postgres md5
* If you can't find this file, running locate pg_hba.conf should show you where ...
Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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