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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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How default .equals and .hashCode will work for my classes?
...the default implementation is Object's (generally speaking; if you inherit from a class that redefined equals and/or hashCode, then you'll use that implementation instead).
From the documentation:
equals
The equals method for class Object implements the most discriminating possible equivalence...
Bootstrap 3 Glyphicons are not working
...ly help others.
Something was wrong with the font files that I downloaded from Bootstrap 3's customizer tool. To get the correct fonts, go to the Bootstrap homepage and download the full .zip file. Extract the four font files from there to your fonts directory and everything should work.
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What do the result codes in SVN mean?
...ommit)
S: This signifies that the file or directory has been switched from the path of the rest of the working copy (using svn switch) to a
branch
I: Ignored
X: External definition
~: Type changed
R: Item has been replaced in your working copy. This means the file was sche...
What is the difference between typeof and instanceof and when should one be used vs. the other?
..."function" object and instanceof will fail if you try to compare an object from another (i)frame/window. typeof will work in all cases since it returns the string "function".
– some
May 23 '09 at 16:56
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How to convert an OrderedDict into a regular dict in python3
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>>> from collections import OrderedDict
>>> OrderedDict([('method', 'constant'), ('data', '1.225')])
OrderedDict([('method', 'constant'), ('data', '1.225')])
>>> dict(OrderedDict([('method', 'constant'), ('data'...
Changing Mercurial “Default” Parent URL
Let's say I have a Mercurial repository and I'm pulling from a default parent URL (the source I cloned it from).
3 Answers
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How to get commit history for just one branch?
Let's say I created a new branch my_experiment from master and made several commits to my_experiment . If I do a git log when on my_experiment , I see the commits made to this branch, but also the commits made to master before the my_experiments branch was created.
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Difference between rake db:migrate db:reset and db:schema:load
... The thing which I don't understand is how rake db:schema:load different from the former two.
5 Answers
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How do I turn a python datetime into a string, with readable format date?
...mplish the same using python's general formatting function...
>>>from datetime import datetime
>>>"{:%B %d, %Y}".format(datetime.now())
The formatting characters used here are the same as those used by strftime. Don't miss the leading : in the format specifier.
Using format() ...