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How to import other Python files?
How do I import other files in Python?
19 Answers
19
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Time complexity of Sieve of Eratosthenes algorithm
...cals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound is n(1/2 + 1/3 + 1/5 + 1/7 + …), that is sum of reciprocals of primes up to n, which is O(n log log n). (See here or here.)
The "find the next prime number" bit is only O(n) overall, amortized — yo...
Video auto play is not working in Safari and Chrome desktop browser
...getElementById('vid').play();
</script>
...not pretty but somehow works.
UPDATE
Recently many browsers can only autoplay the videos with sound off, so you'll need to add muted attribute to the video tag too
<video autoplay muted>
...
</video>
...
Google Map API V3: How to add Custom data to markers
Is there a way I can add some custom information to my markers for later use. There are ways to have an info-window and a title, but what If I want to associate the marker with other information.
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Print a file, skipping the first X lines, in Bash [duplicate]
...very long file which I want to print, skipping the first 1,000,000 lines, for example.
13 Answers
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How do I automatically sort a has_many relationship in Rails?
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You can specify the sort order for the bare collection with an option on has_many itself:
class Article < ActiveRecord::Base
has_many :comments, :order => 'created_at DESC'
end
class Comment < ActiveRecord::Base
belongs_to :artic...
Calling a parent window function from an iframe
...See window.parent
Returns a reference to the parent of the current window or subframe.
If a window does not have a parent, its parent property is a reference to itself.
When a window is loaded in an <iframe>, <object>, or <frame>, its parent is the window with the element embedd...
Efficiently checking if arbitrary object is NaN in Python / numpy / pandas?
...
pandas.isnull() (also pd.isna(), in newer versions) checks for missing values in both numeric and string/object arrays. From the documentation, it checks for:
NaN in numeric arrays, None/NaN in object arrays
Quick example:
import pandas as pd
import numpy as np
s = pd.Series(['...
Nested function in C
...
No, they don't exist in C.
They are used in languages like Pascal for (at least) two reasons:
They allow functional decomposition without polluting namespaces. You can define a single publicly visible function that implements some complex logic by relying one or more nested functions to br...
What is the difference between Fragment and FragmentActivity?
... which has:
its own lifecycle
receives its own input events
can be added or removed while the Activity is running.
A Fragment must always be embedded in an Activity.
Fragments are not part of the API prior to HoneyComb (3.0). If you want to use Fragments in an app targeting a platform version ...