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Calculating arithmetic mean (one type of average) in Python
... return float(sum(numbers)) / max(len(numbers), 1)
>>> mean([1,2,3,4])
2.5
>>> mean([])
0.0
In numpy, there's numpy.mean().
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How to get an array of specific “key” in multidimensional array without looping
... must support php > 5.5, the following alternatives exist:
Since php 5.3, you can use array_map with an anonymous function, like this:
$ids = array_map(function ($ar) {return $ar['id'];}, $users);
Before(Technically php 4.0.6+), you must create an anonymous function with create_function inste...
Best way to convert string to bytes in Python 3?
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3 Answers
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How can I return pivot table output in MySQL?
...ot` (
`pid` bigint(20) NOT NULL AUTO_INCREMENT,
`company_name` varchar(32) DEFAULT NULL,
`action` varchar(16) DEFAULT NULL,
`pagecount` bigint(20) DEFAULT NULL,
PRIMARY KEY (`pid`)
) ENGINE=MyISAM;
Now look into his/her desired table:
company_name EMAIL PRINT 1 pages PRINT 2 page...
Convert JavaScript string in dot notation into an object reference
...that will be displayed to the user. Like using a date as a string "1999-12-30" rather than a Date object (which can cause timezone bugs or added serialization complexity if not careful). Or you know what you're doing.
This is maybe fine. Be careful that there are no dot strings "." in your s...
How to format all Java files in an Eclipse project at one time?
...root and select Source -> Format. This should work for at least version 3.8.1. and above.
If the above does not work, you're probably using an older Eclipse-version. In such case you can select your Source Folders by clicking on them while holding down CTRL, then select Source -> Format from ...
How to redirect output with subprocess in Python?
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UPDATE: os.system is discouraged, albeit still available in Python 3.
Use os.system:
os.system(my_cmd)
If you really want to use subprocess, here's the solution (mostly lifted from the documentation for subprocess):
p = subprocess.Popen(my_cmd, shell=True)
os.waitpid(p.pid, 0)
OTOH,...
str performance in python
While profiling a piece of python code ( python 2.6 up to 3.2 ), I discovered that the
str method to convert an object (in my case an integer) to a string is almost an order of magnitude slower than using string formatting.
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Python Empty Generator Function
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You can use return once in a generator; it stops iteration without yielding anything, and thus ...