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Representing graphs (data structure) in Python

...f._graph[node2].add(node1) def remove(self, node): """ Remove all references to node """ for n, cxns in self._graph.items(): # python3: items(); python2: iteritems() try: cxns.remove(node) except KeyError: pass tr...
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How to get the request parameters in Symfony 2?

... The naming is not all that intuitive: use Symfony\Component\HttpFoundation\Request; public function updateAction(Request $request) { // $_GET parameters $request->query->get('name'); // $_POST parameters $request->r...
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Count the number occurrences of a character in a string

...e counts for a lot of the letters in a given string, Counter provides them all in a more succinct form. If you want the count for one letter from a lot of different strings, Counter provides no benefit. – Brenden Brown Feb 17 '15 at 19:30 ...
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Make elasticsearch only return certain fields?

...fields from there. May impact performance if returned data is relatively small to the size of a whole document. – Zaar Hai Aug 18 '13 at 10:19 ...
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How to convert CFStringRef to NSString?

...n objects with +1 reference counts, meaning that they need to be released (all CF[Type]Create format functions do this). The nice thing is that in Cocoa you can safely use autorelease or release to free them up. share ...
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What are some uses of template template parameters?

...alue) { } Here, H is a template, but I wanted this function to deal with all specializations of H. NOTE: I've been programming c++ for many years and have only needed this once. I find that it is a rarely needed feature (of course handy when you need it!). I've been trying to think of good examp...
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When is assembly faster than C?

...hat although that's not entirely false, the cases where assembler can actually be used to generate more performant code are both extremely rare and require expert knowledge of and experience with assembly. ...
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capturing self strongly in this block is likely to lead to a retain cycle

... Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
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Getter and Setter?

... That's not really setter and getter. Typically I need for each property different implementation of getter! – sumid Feb 16 '13 at 0:59 ...
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How to check if a python module exists without importing it

...ING When trying to find a submodule, it will import the parent module (for all of the above methods)! food/ |- __init__.py |- eggs.py ## __init__.py print("module food loaded") ## eggs.py print("module eggs") were you then to run >>> import importlib >>> spam_spec = importli...