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Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...
is is identity testing, == is equality testing. what happens in your code would be emulated in the interpreter like this:
>>> a = 'pub'
>>> b = ''.join(['p', 'u', 'b'])
>>> a == b
True
>>> a is b
False
...
Use numpy array in shared memory for multiprocessing
...mport SharedArray as sa
# Create an array in shared memory
a = sa.create("test1", 10)
# Attach it as a different array. This can be done from another
# python interpreter as long as it runs on the same computer.
b = sa.attach("test1")
# See how they are actually sharing the same memory block
a[0]...
Creating a ZIP Archive in Memory Using System.IO.Compression
..."Bar!");
}
}
using (var fileStream = new FileStream(@"C:\Temp\test.zip", FileMode.Create))
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
So we need to call dispose on ZipArchive before we can use it, which means passing 'true' as the ...
How to filter array in subdocument with MongoDB [duplicate]
...er individual elements and then use $group to put it back together:
db.test.aggregate([
{ $match: {_id: ObjectId("512e28984815cbfcb21646a7")}},
{ $unwind: '$list'},
{ $match: {'list.a': {$gt: 3}}},
{ $group: {_id: '$_id', list: {$push: '$list.a'}}}
])
outputs:
{
"result": [
...
How can one use multi threading in PHP applications
...ng in PHP should therefore remain to CLI-based applications only.
Simple Test
#!/usr/bin/php
<?php
class AsyncOperation extends Thread {
public function __construct($arg) {
$this->arg = $arg;
}
public function run() {
if ($this->arg) {
$sleep = m...
How to use Elasticsearch with MongoDB?
...ttachments/1.6.0
These two plugins aren't necessary but they're good for testing queries and visualizing changes to your indexes.
bin/plugin --install mobz/elasticsearch-head
bin/plugin --install lukas-vlcek/bigdesk
Restart Elasticsearch.
sudo service elasticsearch restart
Finally index a co...
machine learning libraries in C# [closed]
...o create the '.Net version' of weka, then you can try to run the following tests:
[Fact]
public void BuildAndClassify()
{
var classifier = BuildClassifier();
AssertCanClassify(classifier);
}
[Fact]
public void DeserializeAndClassify()
{
BuildClassifier().Serialize("test.weka");
var classif...
Append an object to a list in R in amortized constant time, O(1)?
...(amount of memory consumed) as a problem size grows. Running a performance test for various solutions given a fixed-size problem does not address the various solutions' growth rate. The OP is interested in knowing if there is a way to append objects to an R list in "amortized constant time". What do...
Clang vs GCC for my Linux Development project
...rious benchmarks where clang pretty much blew gcc out of the water in ever test. Source: clang.llvm.org/features.html#performance
– user562566
Dec 8 '11 at 0:29
...
What is __init__.py for?
...was required under Python 2.X and is still required under Python 2.7.12 (I tested it) but it is no longer required from (allegedly) Python 3.3 onwards, and is not required under Python 3.4.3 (I tested it). See stackoverflow.com/questions/37139786 for more details.
– Rob_before...