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What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
...
The first version is preferable:
It works for all kinds of keys, so you can, for example, say {1: 'one', 2: 'two'}. The second variant only works for (some) string keys. Using different kinds of syntax depending on the type of the keys would be an unnecessary inconsisten...
Interface defining a constructor signature?
...ult in Google some 7 years later, I thought I would chip in here - specifically to show how you could use an abstract base class in tandem with your existing Interface and maybe cut down on the amount of refactoring needed in the future for similar situations. This concept has already been hinted a...
How to get the current directory in a C program?
...re out of touch.
– gbtimmon
Feb 22 '16 at 2:55
3
Code snippet: man 3 getcwd. Jokes aside, don't b...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
How to make a PHP SOAP call using the SoapClient class
...gh.
– Cameron Chapman
Aug 26 '13 at 16:14
4
@user should accept it :) BTW, very nice answer, comp...
What is stdClass in PHP?
... class, kind of like Object in Java or object in Python (Edit: but not actually used as universal base class; thanks @Ciaran for pointing this out).
It is useful for anonymous objects, dynamic properties, etc.
An easy way to consider the StdClass is as an alternative to associative array. See thi...
How to resolve “must be an instance of string, string given” prior to PHP 7?
... supposed to work to begin with. Given the dynamic typing system, this actually makes some sort of perverted sense.
You can only manually "type hint" scalar types:
function foo($string) {
if (!is_string($string)) {
trigger_error('No, you fool!');
return;
}
...
}
...
Calculate distance between two points in google maps V3
...
@EmanuelePaolini - Mathematically, atan2(sqrt(a),sqrt(1-a)) = asin(sqrt(a)) = acos(sqrt(1-a)), but the atan2 version remains numerically better conditioned for all values of a.
– ChrisV
Dec 19 '14 at 18:00
...
What is the difference between native code, machine code and assembly code?
...ece of metal that does the actual work) understands and executes directly. All other code must be translated or transformed into machine code before your machine can execute it.
Native code: This term is sometimes used in places where machine code (see above) is meant. However, it is also sometimes...
Send message to specific client with socket.io and node.js
..."I'm the master", function() {
// Save the socket id to Redis so that all processes can access it.
client.set("mastersocket", socket.id, function(err) {
if (err) throw err;
console.log("Master socket is now" + socket.id);
});
});
socket.on("message to master", function(...