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How does Dijkstra's Algorithm and A-Star compare?
...t; but it is a special case of the more general algorithm A*. It is not at all unusual (in fact, probably the norm) for special cases to be discovered first, and then subsequently be generalized .
– Pieter Geerkens
Sep 2 '13 at 15:37
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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
Refresh a page using PHP
How can I refresh a page using PHP periodically? If I can not do it by PHP, what is the best recommended scenario?
13 Answe...
How do I get a file extension in PHP?
...non ASCII characters, you need to set the locale first. E.G:
setlocale(LC_ALL,'en_US.UTF-8');
Also, note this doesn't take into consideration the file content or mime-type, you only get the extension. But it's what you asked for.
Lastly, note that this works only for a file path, not a URL resou...
Convert a list of data frames into one data frame
I have code that at one place ends up with a list of data frames which I really want to convert to a single big data frame.
...
How do I update/upsert a document in Mongoose?
...
Mongoose now supports this natively with findOneAndUpdate (calls MongoDB findAndModify).
The upsert = true option creates the object if it doesn't exist. defaults to false.
var query = {'username': req.user.username};
req.newData.username = req.user.username;
MyModel.findOneAndUpd...
How do I initialize the base (super) class?
... and invoke their base class through super(), e.g.
class X(object):
def __init__(self, x):
pass
def doit(self, bar):
pass
class Y(X):
def __init__(self):
super(Y, self).__init__(123)
def doit(self, foo):
return super(Y, self).doit(foo)
Because python knows about old- an...
Height equal to dynamic width (CSS fluid layout) [duplicate]
...
All you need to do is include the jQuery script and css styles. Check full code at jsfiddle.net/n6DAu/24
– Hussein
Jul 28 '11 at 6:12
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Delete a key from a MongoDB document using Mongoose
...de-mongodb-native driver. Each model has a collection object that contains all the methods that node-mongodb-native offers. So you can do the action in question by this:
User.collection.update({_id: user._id}, {$unset: {field: 1 }});
Since version 2.0 you can do:
User.update({_id: user._id}, {$u...
Capture characters from standard input without waiting for enter to be pressed
...oo much on the terminal used that may be connected with stdin (they are usually line buffered). You can, however use a library for that:
conio available with Windows compilers. Use the _getch() function to give you a character without waiting for the Enter key. I'm not a frequent Windows developer...