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How to get the nth element of a python list or a default if not available
I'm looking for an equivalent in python of dictionary.get(key, default) for lists. Is there any one liner idiom to get the nth element of a list or a default value if not available?
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Reading a huge .csv file
I'm currently trying to read data from .csv files in Python 2.7 with up to 1 million rows, and 200 columns (files range from 100mb to 1.6gb). I can do this (very slowly) for the files with under 300,000 rows, but once I go above that I get memory errors. My code looks like this:
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Dependency injection with Jersey 2.0
Starting from scratch without any previous Jersey 1.x knowledge, I'm having a hard time understanding how to setup dependency injection in my Jersey 2.0 project.
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How to take column-slices of dataframe in pandas
I load some machine learning data from a CSV file. The first 2 columns are observations and the remaining columns are features.
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What is the function __construct used for?
I have been noticing __construct a lot with classes. I did a little reading and surfing the web, but I couldn't find an explanation I could understand. I am just beginning with OOP.
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What is getattr() exactly and how do I use it?
... The problem is that I still can't grasp the idea of its usage. The only thing I understand about getattr() is that getattr(li, "pop") is the same as calling li.pop .
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Adding :default => true to boolean in existing Rails column
I've seen a few questions (namely this one ) here on SO about adding a default boolean value to an existing column. So I tried the change_column suggestion but I mustn't be doing it right.
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How do I add PHP code/file to HTML(.html) files?
I can't use PHP in my HTML pages. For example, index.html . I've tried using both:
12 Answers
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Is there a standard sign function (signum, sgn) in C/C++?
...i/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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How to check if an object is serializable in C#
I am looking for an easy way to check if an object in C# is serializable.
9 Answers
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