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How do I build a numpy array from a generator?
... lists. This is necessary so that space for each item can be consecutively allocated in memory. Consecutive allocation is the key feature of numpy arrays: this combined with native code implementation let operations on them execute much quicker than regular lists.
Keeping this in mind, it is techni...
Design patterns or best practices for shell scripts [closed]
...first suggestion is "don't". The reason is that is fairly easy to make a small mistake that hinders your script, or even make it dangerous.
That said, I don't have other resources to pass you but my personal experience.
Here is what I normally do, which is overkill, but tends to be solid, although...
How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
... contains a text column named Details . (Yes, I realize this should actually be a varchar(MAX) column, but whoever set this database up did not do it that way.)
...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
...$dev/statistics";
my %stats = do {
opendir +(my $dh), $dir;
local @_ = readdir $dh;
closedir $dh;
map +($_, []), grep !/^\.\.?$/, @_;
};
if (-t STDOUT) {
while (1) {
print "\033[H\033[J", run();
my ($time, $us) = gettimeofday();
my ($sec, $min, $hour) = l...
How do I get the number of elements in a list?
...turns 3.
Explanation
Everything in Python is an object, including lists. All objects have a header of some sort in the C implementation.
Lists and other similar builtin objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is...
How to exclude certain directories/files from git grep search
...va files from under your current directory).
There's a good reference for all the "magic words" allowed in a pathspec at git-scm.com (or just git help glossary). For some reason, the docs at kernel.org are really out of date even though they often come up first in google searches.
...
How do I achieve the theoretical maximum of 4 FLOPs per cycle?
... while (i < 1000){
// Here's the meat - the part that really matters.
r0 = _mm_mul_pd(r0,rC);
r1 = _mm_add_pd(r1,rD);
r2 = _mm_mul_pd(r2,rE);
r3 = _mm_sub_pd(r3,rF);
r4 = _mm_mul_pd(r4,rC);
r5 = _mm_add_pd(r5...
Can I extend a class using more than 1 class in PHP?
...
Answering your edit :
If you really want to fake multiple inheritance, you can use the magic function __call().
This is ugly though it works from class A user's point of view :
class B {
public function method_from_b($s) {
echo $s;
}
}
c...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...languages or characters.
On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.
Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci
utf8mb4_unicode_ci, which uses the Unicode r...
Grepping a huge file (80GB) any way to speed it up?
...
Here are a few options:
1) Prefix your grep command with LC_ALL=C to use the C locale instead of UTF-8.
2) Use fgrep because you're searching for a fixed string, not a regular expression.
3) Remove the -i option, if you don't need it.
So your command becomes:
LC_ALL=C fgrep -A 5 -...