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Is it better to use std::memcpy() or std::copy() in terms to performance?
... of std::copy over memcpy: 2.99%
My compiler is gcc 4.6.3 on Fedora 16 x86_64. My optimization flags are -Ofast -march=native -funsafe-loop-optimizations.
Code for my SHA-2 implementations.
I decided to run a test on my MD5 implementation as well. The results were much less stable, so I decided t...
Combine two ActiveRecord::Relation objects
...
If you want to combine using AND (intersection), use merge:
first_name_relation.merge(last_name_relation)
If you want to combine using OR (union), use or†:
first_name_relation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install the where-or backport.
...
iOS UIImagePickerController result image orientation after upload
....size.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
transform = CGAffineTransformTranslate(transform, self.size.width, 0);
transform = CGAffineTr...
Insert auto increment primary key to existing table
I am trying to alter a table which has no primary key nor auto_increment column. I know how to add an primary key column but I was wondering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it man...
How to pull a random record using Django's ORM?
...
Using order_by('?') will kill the db server on the second day in production. A better way is something like what is described in Getting a random row from a relational database.
from django.db.models.aggregates import Count
from random...
Convert JavaScript string in dot notation into an object reference
... given somewhere (e.g. developer.mozilla.org/en/JavaScript/Reference/Global_Objects/… ).
– ninjagecko
Jun 18 '11 at 6:12
...
URL Encoding using C#
... %5E %5E ^ ^ %5E
_ _ _ _ _ _ _ _ %5F
` %60 %60 ` %60 %60 ` ...
How to find server name of SQL Server Management Studio
...re was an option to create servers as well. Now it's working. Microsft, ¯\_(ツ)_/¯
– adiga
Jan 3 '18 at 7:05
...
powershell 2.0 try catch how to access the exception
....downloadString('http://foo')
}
catch [Net.WebException] {
Write-Host $_.Exception.ToString()
}
The exception is in the $_ variable. You might explore $_ like this:
try {
$w = New-Object net.WebClient
$d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
$_ | fl * -For...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
... operator.
if ((unsigned)(number-lower) <= (upper-lower))
in_range(number);
With a typical, modern computer (i.e., anything using twos complement), the conversion to unsigned is really a nop -- just a change in how the same bits are viewed.
Note that in a typical case, you can pre-...