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Calculating arithmetic mean (one type of average) in Python
Is there a built-in or standard library method in Python to calculate the arithmetic mean (one type of average) of a list of numbers?
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Bash tool to get nth line from a file
...e been wondering if there's a Bash tool that specifically extracts a line (or a range of lines) from a file.
19 Answers
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What is the difference between buffer and cache memory in Linux?
To me it's not clear what's the difference between the two Linux memory concepts : buffer and cache . I've read through this post and it seems to me that the difference between them is the expiration policy:
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Java unchecked: unchecked generic array creation for varargs parameter
... unchecked warnings in my Java code, but I am failing to understand the error on the following lines:
2 Answers
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Is there a cross-browser onload event when clicking the back button?
For all major browsers (except IE), the JavaScript onload event doesn’t fire when the page loads as a result of a back button operation — it only fires when the page is first loaded.
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Handle Guzzle exception and get HTTP body
I would like to handle errors from Guzzle when the server returns 4xx and 5xx status codes. I make a request like this:
5 A...
How to get the file extension in PHP? [duplicate]
...d to use string functions. You can use something that's actually designed for what you want: pathinfo():
$path = $_FILES['image']['name'];
$ext = pathinfo($path, PATHINFO_EXTENSION);
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impro...
How to create a protocol with methods that are optional?
...s defined in the iPhone SDK, such as the UIActionSheetDelegate protocol for example.
5 Answers
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Filtering a list of strings based on contents
...as follows:
>>> lst = ['a', 'ab', 'abc', 'bac']
>>> [k for k in lst if 'ab' in k]
['ab', 'abc']
Another way is to use the filter function. In Python 2:
>>> filter(lambda k: 'ab' in k, lst)
['ab', 'abc']
In Python 3, it returns an iterator instead of a list, but you c...
How to change the playing speed of videos in HTML5?
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According to this site, this is supported in the playbackRate and defaultPlaybackRate attributes, accessible via the DOM. Example:
/* play video twice as fast */
document.querySelector('video').defaultPlaybackRate = 2.0;
docume...