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How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
...
Turning off some legends in a ggplot
...
You can use guide=FALSE in scale_..._...() to suppress legend.
For your example you should use scale_colour_continuous() because length is continuous variable (not discrete).
(p3 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +
sca...
ipython: print complete history (not just current session)
...
First use %hist -o -g -f ipython_history.md to output the history (input and output) to a text file. (http://ipython.readthedocs.io/en/stable/interactive/magics.html#magic-history)
Then you can use the the get_session_info function to retreive the date and...
Java: parse int value from a char
...So e.g. '0' in ascii is 48, '1' is 49, etc. So if you take '2' - '0' you really just get 50 - 48 = 2. Have a look at an ASCII table in order to understand this principle better. Also, 'x' means get the ascii value of the character in Java.
– Kevin Van Ryckegem
...
What is the correct way of using C++11's range-based for?
...x << ' ';
}
the output is something like:
[... copy constructor calls for vector<X> initialization ...]
Elements:
X copy ctor.
1 X copy ctor.
3 X copy ctor.
5 X copy ctor.
7 X copy ctor.
9
As it can be read from the output, copy constructor calls are made during range-based for l...
How to convert string representation of list to a list?
... ast
>>> x = u'[ "A","B","C" , " D"]'
>>> x = ast.literal_eval(x)
>>> x
['A', 'B', 'C', ' D']
>>> x = [n.strip() for n in x]
>>> x
['A', 'B', 'C', 'D']
ast.literal_eval:
With ast.literal_eval, you can safely evaluate an expression node or a string c...
Finding child element of parent pure javascript
...esire.
Edit: Now that I think about it, you could just use querySelectorAll to get decendents of parent having a class name of child1:
children = document.querySelectorAll('.parent .child1');
The difference between qS and qSA is that the latter returns all elements matching the selector, while...
LINQ: Select an object and change some properties without creating a new object
...erties of a LINQ query result object without creating a new object and manually setting every property. Is this possible?
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How to search in array of object in mongodb
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Use $elemMatch to find the array of particular object
db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})
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Python Nose Import Error
...stem path. The following fixed this:
source myvirtualenv/activate
pip install nose
which nosetests
/home/me/myvirtualenv/bin/nosetests
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