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Python unittest - opposite of assertRaises?
...the correct solution in fact. The solution proposed by user9876 is conceptually flawed: if you test for the non-raising of say ValueError, but ValueError is instead raised, your test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise ...
Principal component analysis in Python
...
Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
What is the purpose of class methods?
...sson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
17 Answers
...
What is the effect of extern “C” in C++?
...very compiler is required to provide "C" linkage
A linkage specification shall occur only in namespace scope
All function types, function names and variable names have a language linkage See Richard's Comment: Only function names and variable names with external linkage have a language linkage
Two ...
Delete all documents from index/type without deleting type
I know one can delete all documents from a certain type via deleteByQuery.
15 Answers
...
std::function and std::bind: what are they, and when should they be used?
...nd to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that almost does the job yo...
jQuery find events handlers registered with an object
..."
$.each(event, function(j, h) {
// h.handler is the function being called
});
});
Here's an example you can play with:
$(function() {
$("#el").click(function(){ alert("click"); });
$("#el").mouseover(function(){ alert("mouseover"); });
$.each($._data($("#el")[0], "events")...
Chrome desktop notification example [closed]
...g as the page is open, and may disappear automatically after a few seconds
Service Worker notifications - a bit more complicated, but they can work in the background (even after the page is closed), are persistent, and support action buttons
The API call takes the same parameters (except for actio...
What is the difference between join and merge in Pandas?
...
pandas.merge() is the underlying function used for all merge/join behavior.
DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...
django test app error - Got an error creating the test database: permission denied to create databas
...3306',
}
}
and my docker-compose.yml looks as follows:
version: '3'
services:
web:
build: .
command: './wait_for_db_and_start_server.sh'
env_file: env_web
working_dir: /project_name
links:
- db
volumes:
- .:/volume_name
ports:
...