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Mapping over values in a python dictionary
..., f(kv[1])), my_dictionary.iteritems()))
but that's not that readable, really.
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Positioning MKMapView to show multiple annotations at once
...tations I want to add to my MKMapView (it could 0-n items, where n is generally around 5). I can add the annotations fine, but I want to resize the map to fit all annotations onscreen at once, and I'm not sure how to do this.
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How to inherit from a class in javascript?
...t the bottom. I now prefer Object.create(). Object.create is available in all modern browsers.
I should note that Object.create is usually much slower than using new with a function constructor.
//The prototype is just an object when you use `Object.create()`
var Base = {};
//This is how you cre...
In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
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Note that groupname can also be the ac...
Multiprocessing vs Threading Python [duplicate]
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There is actually a good deal of difference: eli.thegreenplace.net/2012/01/16/…
– Andrew Sledge
May 29 '13 at 11:36
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Best practice: PHP Magic Methods __set and __get [duplicate]
...magic methods.
This was a mistake, the last part of your question says it all :
this is slower (than getters/setters)
there is no auto-completion (and this is a major problem actually), and type management by the IDE for refactoring and code-browsing (under Zend Studio/PhpStorm this can be handle...
mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
Inserting multiple rows in mysql
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When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.
Optimizing INSERT Statements
You can find more tips on how to speed up your insert statements on the link above.
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Understanding the difference between Object.create() and new SomeFunction()
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The object used in Object.create actually forms the prototype of the new object, where as in the new Function() form the declared properties/functions do not form the prototype.
Yes, Object.create builds an object that inherits directly from the one passed as ...
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
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and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True.
In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...