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How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Getting distance between two points based on latitude/longitude
...just on answering the specific bug OP ran into.
It's because in Python, all the trig functions use radians, not degrees.
You can either convert the numbers manually to radians, or use the radians function from the math module:
from math import sin, cos, sqrt, atan2, radians
# approximate radiu...
lodash multi-column sortBy descending
...dash.com/docs#orderBy) in Lodash as of 4.3.0. The normal sort function is called _.sortBy(lodash.com/docs#sortBy)
– Nidhin David
Feb 12 '16 at 11:19
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How to enable C++11/C++0x support in Eclipse CDT?
..., find the Preprocessor Include Path and go to the Providers Tab. Deselect all except CDT GCC Builtin Compiler Settings. Then untag Share settings entries … . Add the option -std=c++11 to the text box called Command to get compiler specs.
Go to paths and symbols. Under Symbols, click restore defau...
How to find elements by class
...h to only find those divs with a given class using BS3:
mydivs = soup.findAll("div", {"class": "stylelistrow"})
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Meaning of @classmethod and @staticmethod for beginner? [duplicate]
...ect as the first parameter, whereas staticmethod can have no parameters at all.
Example
class Date(object):
def __init__(self, day=0, month=0, year=0):
self.day = day
self.month = month
self.year = year
@classmethod
def from_string(cls, date_as_string):
...
How do you build a Singleton in Dart?
... There's the weird syntax Singleton._internal(); that looks like a method call when it's really a constructor definition. There's the _internal name. And there's the nifty language design point that Dart lets you start out (dart out?) using an ordinary constructor and then, if needed, change it to a...
Extract value of attribute node via XPath
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With xqilla it was necessary to call xs:string. I wonder why.
– krlmlr
Jul 22 '13 at 20:00
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How to change Rails 3 server default port in develoment?
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First - do not edit anything in your gem path! It will influence all projects, and you will have a lot problems later...
In your project edit script/rails this way:
#!/usr/bin/env ruby
# This command will automatically be run when you run "rails" with Rails 3 gems installed from the root...
Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...