magic-methods

def pi(): prompt=">>> " print "\nWARNING: Pi may take some time to be calculated and may not always be correct beyond 100 digits." print "\nShow Pi to what digit?" n=raw_input(prompt) from decimal import Decimal, localcontext with localcontext() as ctx: ctx.prec = 10000 pi = Decimal(0) for k in range(350): pi += (Decimal(4)/(Decimal(8)*k+1) - Decimal(2)/(Decimal(8)*k+4) - Decimal(1)/(Decimal(8)*k+5) - Decimal(1)/(Decimal(8)*k+6)) / Decimal(16)**k print pi[:int(n)] pi() Traceback (most recent call last): File "/Users/patrickcook/Documents/Pi", line 13, in <module> pi() File "/Users/patrickcook

I have a custom-built MVC PHP framework that I am in the process of rewriting and had a question about performance and magic methods. With the model portion of the framework, I was thinking if __get / __set magic methods would cause too much performance hit to be worth using. I mean accessing (reads and writes) model data is going to be one of the most common things performed. Is the use of __get / __set magic methods too big of a performance hit for heavy use functionality like the model portion of a MVC framework? Measure it. It certainly has a big performance hit, especially considering

Where is a complete list of the special double-underscore/dunder methods that can be used in classes? (e.g., __init__ , __new__ , __len__ , __add__ ) Please take a look at the special method names section in the Python language reference. Jonny Buchanan Dive Into Python has an excellent appendix for them. If, like me, you want a plain, unadorned list, here it is. I compiled it based on the Python documentation link from the accepted answer. __abs__ __add__ __and__ __call__ __class__ __cmp__ __coerce__ __complex__ __contains__ __del__ __delattr__ __delete__ __delitem__ __delslice__ __dict__ _

I am playing with numpy and digging through documentation and I have come across some magic. Namely I am talking about numpy.where() : >>> x = np.arange(9.).reshape(3, 3) >>> np.where( x > 5 ) (array([2, 2, 2]), array([0, 1, 2])) How do they achieve internally that you are able to pass something like x > 5 into a method? I guess it has something to do with __gt__ but I am looking for a detailed explanation. How do they achieve internally that you are able to pass something like x > 5 into a method? The short answer is that they don't. Any sort of logical operation on a numpy array returns a

After many happy years coding in notepad++ and sublime, I've been advised to give a PHP IDE a go. I'm trying out phpStorm and it seems nice. The code completion and documentation is a great feature but isn't working out for me when magic methods are used. Is there a work around to get phpStorm to understand what's going on in magic methods? Our situation is something like this: abstract class a { public static function __callStatic($method,$args) { if(strpos($method,"get_by_") === 0) { //do stuff } elseif(strpos($method,"get_first_by_") === 0) { //do stuff } elseif($method == "get_all") { //do

In addition to bypassing any instance attributes in the interest of correctness, implicit special method lookup generally also bypasses the __getattribute__() method even of the object’s metaclass. The docs mention special methods such as __hash__ , __repr__ and __len__ , and I know from experience it also includes __iter__ for Python 2.7. To quote an answer to a related question : "Magic __methods__() are treated specially: They are internally assigned to "slots" in the type data structure to speed up their look-up, and they are only looked up in these slots." In a quest to improve my answer