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What is in your Mathematica tool bag? [closed]
...and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and transform them in the process. The way it works is that a criteria function (f...
What exactly does Perl's “bless” do?
...
package Person;
sub new
{
my $class = shift;
my $self = {
_firstName => shift,
_lastName => shift,
_ssn => shift,
};
# Print all the values just for clarification.
print "First Name is $self->{_firstName}\n";
print "Last Name is $se...
How to find out if an installed Eclipse is 32 or 64 bit version?
...e the line with text:
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.0.200.v20090519
then it is 64 bit.
If it would be plugins/org.eclipse.equinox.launcher.win32.win32.x86_32_1.0.200.v20090519 then it is 32 bit.
...
Dynamically set local variable [duplicate]
... out in the comments there are exceptions, for example classes that define __slots__). Function locals can be optimised for speed because the compiler (usually) knows all the names in advance, so there isn't a dictionary until you call locals().
In the C implementation of Python locals() (called fr...
What is an alternative to execfile in Python 3?
...me on Python3.3. I get "No such file or directory" when I exec(open('./some_file').read()). I have tried including the '.py' extension and also excluding the './' as well
– JoeyC
Feb 20 '14 at 0:20
...
Is there a WebSocket client implemented for Python? [closed]
...ient
Sample client code:
#!/usr/bin/python
from websocket import create_connection
ws = create_connection("ws://localhost:8080/websocket")
print "Sending 'Hello, World'..."
ws.send("Hello, World")
print "Sent"
print "Receiving..."
result = ws.recv()
print "Received '%s'" % result
ws.close()
S...
How to access and test an internal (non-exports) function in a node.js module?
...
var app = rewire('../application/application.js');
var logError = app.__get__('logMongoError');
describe('Application module', function() {
it('should output the correct error', function(done) {
logError().should.equal('MongoDB Connection Error. Please make sure that MongoDB is runni...
Why does “_” (underscore) match “-” (hyphen)?
...
Because the underscore _ is a wildcard like the percent %, except that it only looks for one character.
SQL pattern matching enables you to use "_" to match any single character and "%" to match an arbitrary number of characters (including zero...
In where shall I use isset() and !empty()
.....) contains some non-empty data.
To answer question 1 :
$str = '';
var_dump(isset($str));
gives
boolean true
Because the variable $str exists.
And question 2 :
You should use isset to determine whether a variable exists ; for instance, if you are getting some data as an array, you migh...
How to import a module given the full path?
...
For Python 3.5+ use:
import importlib.util
spec = importlib.util.spec_from_file_location("module.name", "/path/to/file.py")
foo = importlib.util.module_from_spec(spec)
spec.loader.exec_module(foo)
foo.MyClass()
For Python 3.3 and 3.4 use:
from importlib.machinery import SourceFileLoader
fo...