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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
Regex Named Groups in Java
...> TEST
matcher.name(1) ==> login
Replace
matcher.replaceAll("aaaaa_$1_sssss_$2____") ==> aaaaa_TEST_sssss_123____
matcher.replaceAll("aaaaa_${login}_sssss_${id}____") ==> aaaaa_TEST_sssss_123____
(extract from the implementation)
public final class Pattern
implements java.io...
Intro to GPU programming [closed]
Everyone has this huge massively parallelized supercomputer on their desktop in the form of a graphics card GPU.
9 Answers
...
What is function overloading and overriding in php?
...that method.
In PHP, you can only overload methods using the magic method __call.
An example of overriding:
<?php
class Foo {
function myFoo() {
return "Foo";
}
}
class Bar extends Foo {
function myFoo() {
return "Bar";
}
}
$foo = new Foo;
$bar = new Bar;
echo($foo-&...
How can I check if a background image is loaded?
...t it in CSS — so images are start downloading before css file — it's called preloading.
– jcubic
Feb 20 '11 at 17:05
...
What does “The APR based Apache Tomcat Native library was not found” mean?
...ns exactly what it says: "The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path"
The library referred to is bundled into an OS specific dll (tcnative-1.dll) loaded via JNI. It allows tomcat to use OS functionali...
How to determine SSL cert expiration date from a PEM encoded certificate?
...an I query the cert file for when it will expire? Not a web site, but actually the certificate file itself, assuming I have the csr, key, pem and chain files.
...
append multiple values for one key in a dictionary [duplicate]
...st of values associated with that year, right? Here's how I'd do it:
years_dict = dict()
for line in list:
if line[0] in years_dict:
# append the new number to the existing array at this slot
years_dict[line[0]].append(line[1])
else:
# create a new array in this slo...
How to create an object for a Django model with a many to many field?
...
For future visitors, you can create an object and all of its m2m objects in 2 queries using the new bulk_create in django 1.4. Note that this is only usable if you don't require any pre or post-processing on the data with save() methods or signals. What you insert is exactly...
How to save a PNG image server-side, from a base64 data string
...plode(';', $data);
list(, $data) = explode(',', $data);
$data = base64_decode($data);
file_put_contents('/tmp/image.png', $data);
And as a one-liner:
$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));
An efficient method for extracting, decoding, and checking for e...