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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...
add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
Getting list of parameter names inside python function [duplicate]
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Well we don't actually need inspect here.
>>> func = lambda x, y: (x, y)
>>>
>>> func.__code__.co_argcount
2
>>> func.__code__.co_varnames
('x', 'y')
>>>
>>> def func2(x,y=3):
... print(...
How do I catch a numpy warning like it's an exception (not just for testing)?
...ng: divide by zero encountered in divide
array([0])
>>> np.seterr(all='print')
{'over': 'warn', 'divide': 'warn', 'invalid': 'warn', 'under': 'ignore'}
>>> np.array([1])/0 #'print' mode
Warning: divide by zero encountered in divide
array([0])
This means that the warning you see...
How to find the JVM version from a program?
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That JMX call returns the equivalent of "java.vm.version", not "java.version". These are usually (but not necessarily) the same.
– Alex Miller
Jun 21 '13 at 15:54
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How do I check if an object has a specific property in JavaScript?
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I'm really confused by the answers that have been given - most of them are just outright incorrect. Of course you can have object properties that have undefined, null, or false values. So simply reducing the property check to typeo...
Checking images for similarity with OpenCV
...he same image was passed twice, 0% would be returned if the images were totally different.
4 Answers
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jQuery or CSS selector to select all IDs that start with some string [duplicate]
How can I select all elements whose id starts with "player_"?
4 Answers
4
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I want to delete all bin and obj folders to force all projects to rebuild everything
I work with multiple projects, and I want to recursively delete all folders with the name 'bin' or 'obj' that way I am sure that all projects will rebuild everything (sometimes it's the only way to force Visual Studio to forget all about previous builds).
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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...