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Are there any standard exit status codes in Linux?
...tus 2 when called incorrectly (unknown options, wrong number of arguments, etc.) For example, diff -N, grep -Y or diff a b c will all result in $? being set to 2. This is and has been the practice since the early days of Unix in the 1970s.
The accepted answer explains what happens when a command i...
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...
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...
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...
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
...
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 ...
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 =...
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
...
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...
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...