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How do I write data into CSV format as string (not file)?
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You could use StringIO instead of your own Dummy_Writer:
This module implements a file-like class, StringIO, that reads and writes a string buffer (also known as memory files).
There is also cStringIO, which is a faster version of the StringIO class.
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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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How do I reference a javascript object property with a hyphen in it?
...re not allowed in js variables.
This regex pretty much sums it up
[a-zA-Z_$][0-9a-zA-Z_$]*
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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...
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...
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
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Add a new column to existing table in a migration
...lashing with existing models
for Laravel 3:
php artisan migrate:make add_paid_to_users
for Laravel 5+:
php artisan make:migration add_paid_to_users_table --table=users
You then need to use the Schema::table() method (as you're accessing an existing table, not creating a new one). And you ca...
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 autoplay a video using the new embed code style for Youtube?
...ted into key=value pairs by the '&' symbol. en.wikipedia.org/wiki/Query_string#Structure
– knickum
Jan 31 '17 at 19:35
4
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Iterate a list as pair (current, next) in Python
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Since the_list[1:] actually creates a copy of the whole list (excluding its first element), and zip() creates a list of tuples immediately when called, in total three copies of your list are created. If your list is very large, you ...