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How to change the type of a field?
I am trying to change the type of a field from within the mongo shell.
14 Answers
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Check if a given key already exists in a dictionary
I wanted to test if a key exists in a dictionary before updating the value for the key.
I wrote the following code:
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Real world use cases of bitwise operators [closed]
What are some real world use cases of the following bitwise operators?
41 Answers
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Valid to use (anchor tag) without href attribute?
I've been using Twitter Bootstrap to build a site, and a lot of its functionality depends on wrapping things in <a> , even if they're just going to execute Javascript. I've had problems with the href="#" tactic that Bootstrap's documentation recommends, so I was trying to find a different s...
What would a “frozen dict” be?
I guess it could be something like collections.namedtuple , but that is more like a frozen-keys dict (a half-frozen dict). Isn't it?
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Iterate over object attributes in python
I have a python object with several attributes and methods. I want to iterate over object attributes.
8 Answers
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How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
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Algorithm to compare two images
Given two different image files (in whatever format I choose), I need to write a program to predict the chance if one being the illegal copy of another. The author of the copy may do stuff like rotating, making negative, or adding trivial details (as well as changing the dimension of the image).
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How does “cat
I needed to write a script to enter multi-line input to a program ( psql ).
9 Answers
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Getting the last element of a list
In Python, how do you get the last element of a list?
12 Answers
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