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Flask-SQLAlchemy import/context issue

...: # fields here pass And then in your application setup you can call init_app: # apps.application.py from flask import Flask from apps.members.models import db app = Flask(__name__) # later on db.init_app(app) This way you can avoid cyclical imports. This pattern does not necessitate ...
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add column to mysql table if it does not exist

... 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...
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Multiple linear regression in Python

...as some other model evaluation criteria. If you want the stuff like in Akavall's answer, statsmodels has some more R-like diagnostics. – djs Mar 17 '16 at 18:56 ...
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How to create a video from images with FFmpeg?

...pix_fmt yuv420p out.ogg Your images should of course be sorted alphabetically, typically as: 0001-first-thing.jpg 0002-second-thing.jpg 0003-and-third.jpg and so on. I would also first ensure that all images to be used have the same aspect ratio, possibly by cropping them with imagemagick or n...
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How to use timeit module

... The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...
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How do I calculate the date in JavaScript three months prior to today?

...ch 31st the same day as one month before March 28th, 3 days earlier? This all depends on what you mean by "one month before". Go have a conversation with your product owner. If you want to do like momentjs does, and correct these last day of the month errors by moving to the last day of the month...
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Is it possible to make abstract classes in Python?

...nitions of those methods: >>> Abstract() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: Can't instantiate abstract class Abstract with abstract methods foo >>> class StillAbstract(Abstract): ... pass ... >>> StillAbstr...
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Permutations in JavaScript?

... If you notice, the code actually splits the chars into an array prior to do any permutation, so you simply remove the join and split operation var permArr = [], usedChars = []; function permute(input) { var i, ch; for (i = 0; i < inp...
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Remove not alphanumeric characters from string

...e them. A backslash in the string needs escaping if it's to be taken literally: "\\test\\red\\bob\\fred\\new".replace(/\W/g, '') "testredbobfrednew" // output Handling malformed strings If you're not able to escape the input string correctly (why not?), or it's coming from some kind of untruste...
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Git Symlinks in Windows

...es and replaces them with symlinks on windows using mklink. while this actually works for us the --assume-unchanged part doesn't. on switching to another branch git says the symlink files are changed and need to be commited first, while git status says there are no changes..any idea? ...