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How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
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...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
How to load a xib file in a UIView
...
To get an object from a xib file programatically you can use: [[NSBundle mainBundle] loadNibNamed:@"MyXibName" owner:self options:nil] which returns an array of the top level objects in the xib.
So, you could do something like this:
UIView *rootView = [[[NSBundle mai...
What does Redis do when it runs out of memory?
... time finding the answer. How does Redis 2.0 handle running out of maximum allocated memory? How does it decide which data to remove or which data to keep in memory?
...
Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...
Why should I prefer to use member initialization lists?
...tyle. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the construct...
How do I remove a project configuration in Visual Studio 2008?
... wish Visual Studio offered a quicker way to remove a configuration across all projects. If you have a dozen projects or so in a solution it's a pain to go through each of them and manually delete the configuration.
– Stefano Ricciardi
Aug 23 '11 at 9:43
...
Any way to properly pretty-print ordered dictionaries?
...well if you don't care about the order of the keys. Personally, I wish the __repr__ for OrderedDict would produce output like this but preserve the order of the keys.
– ws_e_c421
Sep 24 '15 at 15:54
...
How do I get class name in PHP?
.... I found this out by trying to access the ::class property(?) of a dynamically generated class and getting the following error: Dynamic class names are not allowed in compile-time ::class fetch. See this answer for more details. I also found this note from the docs helpful.
–...