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Is there a way to make mv create the directory to be moved to if it doesn't exist?
... this one-liner (in bash):
mkdir --parents ./some/path/; mv yourfile.txt $_
Breaking that down:
mkdir --parents ./some/path
creates the directory (including all intermediate directories), after which:
mv yourfile.txt $_
moves the file to that directory ($_ expands to the last argument passe...
Array include any value from another array?
....include?(food) }
=> true
Benchmark script:
require "benchmark"
N = 1_000_000
puts "ruby version: #{RUBY_VERSION}"
CHEESES = %w(chedder stilton brie mozzarella feta haloumi).freeze
FOODS = %w(pizza feta foods bread biscuits yoghurt bacon).freeze
Benchmark.bm(15) do |b|
b.report("&, emp...
How do I specify a single test in a file with nosetests?
I have a file called test_web.py containing a class TestWeb and many methods named like test_something().
6 Answers
...
Create list of single item repeated N times
... mutable empty list, set, or dict, you should do something like this:
list_of_lists = [[] for _ in columns]
The underscore is simply a throwaway variable name in this context.
If you only have the number, that would be:
list_of_lists = [[] for _ in range(4)]
The _ is not really special, but y...
Failed to install Python Cryptography package with PIP and setup.py
...he
corresponding locations. For example:
C:\> \path\to\vcvarsall.bat x86_amd64
C:\> set LIB=C:\OpenSSL-1.0.1f-64bit\lib;%LIB%
C:\> set INCLUDE=C:\OpenSSL-1.0.1f-64bit\include;%INCLUDE%
C:\> pip install cryptography
Building cryptography on Linux
cryptography should build very easily on ...
Standard deviation of a list
...calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statistics
>>> statistics.stdev(A_rank)
2.0634114147853952
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Numeric for loop in Django templates
...onal context. Sometimes this comes in handy
{% for i in '0123456789'|make_list %}
{{ forloop.counter }}
{% endfor %}
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How can I use getSystemService in a non-activity class (LocationManager)?
...
You can go for this :
getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
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Converting NSString to NSDate (and back again)
...4, 17))
Goes like:
extension Date
{
public static func FromString(_ dateString: String) -> Date?
{
// Date detector.
let detector = try! NSDataDetector(types: NSTextCheckingResult.CheckingType.date.rawValue)
// Enumerate matches.
var matchedDate: Date...
How do you manage databases in development, test, and production?
...
Name your databases as follows - dev_<<db>> , tst_<<db>> , stg_<<db>> , prd_<<db>> (Obviously you never should hardcode db names
Thus you would be able to deploy even the different type of db's on same physical ...