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Algorithm for creating a school timetable

... classes split in sub-groups some of the time?, Is this a weekly schedule? etc.) there isn't a well known problem class which corresponds to all the scheduling problems. Maybe, the Knapsack problem has many elements of similarity with these problems at large. A confirmation that this is both a har...
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How to become an OpenCart guru? [closed]

...s all products currently in the cart including options, discounted prices, etc. $this->cart->add( $product_id, $qty = 1, $options = array()) - Allows you to add a product to the cart $this->cart->remove( $key ) - Allows you to remove a product from the cart $this->cart->clear() - A...
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What is __init__.py for?

...ons of the package under more convenient name, hold convenience functions, etc. Given the example above, the contents of the init module can be accessed as import spam based on this share | impr...
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How to plot two columns of a pandas data frame using points?

...']) plt.show() # Depending on whether you use IPython or interactive mode, etc. and remember that you can access a NumPy array of the column's values with df.col_name_1.values for example. I ran into trouble using this with Pandas default plotting in the case of a column of Timestamp values with ...
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How to list all installed packages and their versions in Python?

...p._internal but I cant reach it under help(pip._internal), pip.__builtins_ etc. pip reference guide is also blank. – MortenB Sep 10 '18 at 9:48 1 ...
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If isset $_POST

...d the ! operator in cases like this (easier to read, less chance of error, etc.) and reverse the logic... if (empty()) {/* No */} else {/* Yes */} – MrWhite Aug 1 '14 at 10:58 ...
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Mechanisms for tracking DB schema changes [closed]

...le script, update.php, and a number of files numbered 1.sql, 2.sql, 3.sql, etc. The script uses one extra table to store the current version number of the database. The N.sql files are crafted by hand, to go from version (N-1) to version N of the database. They can be used to add tables, add column...
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Project structure for Google App Engine

... datetime import logging import time from google.appengine.api import urlfetch from google.appengine.ext.webapp import template from google.appengine.api import users from google.appengine.ext import webapp from models import * class IndexHandler(webapp.RequestHandler): def get(self): date =...
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What do *args and **kwargs mean? [duplicate]

...to clarify how to unpack the arguments, and take care of missing arguments etc. def func(**keyword_args): #-->keyword_args is a dictionary print 'func:' print keyword_args if keyword_args.has_key('b'): print keyword_args['b'] if keyword_args.has_key('c'): print keyword_args['c'] def f...
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Why does C# forbid generic attribute types?

...y, write lesser code than otherwise required, get benefits of polymorphism etc. //an interface which means it can't have its own implementation. //You might need to use extension methods on this interface for that. public interface ValidatesAttribute<T> { T Value { get; } //or whatever t...