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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to convert An NSInteger to an int?
... front of the NSInteger? For example, (int)myInteger whenever you want to call the integer form, so that you do not have to create a new variable.
– chandhooguy
Dec 28 '14 at 22:05
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Is there a way to make npm install (the command) to work behind proxy?
...roxy variable in a .npmrc file but it does not work. Trying to avoid manually downloading all require packages and installing.
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Best way to assert for numpy.array equality?
..._equal is more reliable.
update
A few versions ago numpy obtained assert_allclose which is now my favorite since it allows us to specify both absolute and relative error and doesn't require decimal rounding as the closeness criterion.
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Doing something before program exit
...t this works great for normal termination of the script, but it won't get called in all cases (e.g. fatal internal errors).
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How to retry after exception?
I have a loop starting with for i in range(0, 100) . Normally it runs correctly, but sometimes it fails due to network conditions. Currently I have it set so that on failure, it will continue in the except clause (continue on to the next number for i ).
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What is `related_name` used for in Django?
... back to your model.
If you don't specify a related_name, Django automatically creates one using the name of your model with the suffix _set, for instance User.map_set.all().
If you do specify, e.g. related_name=maps on the User model, User.map_set will still work, but the User.maps. syntax is ob...
How do I speed up the gwt compiler?
...
Let's start with the uncomfortable truth: GWT compiler performance is really lousy. You can use some hacks here and there, but you're not going to get significantly better performance.
A nice performance hack you can do is to compile for only specific browsers, by inserting the following line in...
Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
How do I use PHP namespaces with autoload?
... $class parameter of autoload is the class name as written in constructor call.
– tishma
Feb 6 '13 at 12:29
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