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How to sort objects by multiple keys in Python?
Or, practically, how can I sort a list of dictionaries by multiple keys?
8 Answers
8
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Calculating distance between two points, using latitude longitude?
...Java code given by Dommer above gives slightly incorrect results but the small errors add up if you are processing say a GPS track. Here is an implementation of the Haversine method in Java which also takes into account height differences between two points.
/**
* Calculate distance between two po...
Remove all special characters from a string in R?
How to remove all special characters from string in R and replace them with spaces ?
3 Answers
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How to convert std::string to lower case?
...a.begin(),
[](unsigned char c){ return std::tolower(c); });
You're really not going to get away without iterating through each character. There's no way to know whether the character is lowercase or uppercase otherwise.
If you really hate tolower(), here's a specialized ASCII-only alternative...
How do I test a file upload in rails?
...ing to make it available on SO.
The rails framework has a function fixture_file_upload (Rails 2 Rails 3, Rails 5), which will search your fixtures directory for the file specified and will make it available as a test file for the controller in functional testing. To use it:
1) Put your file to be ...
How to convert an entire MySQL database characterset and collation to UTF-8?
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@Andrew Large production systems usually have a mirrored DB for maintenance.
– BalusC
Nov 30 '17 at 16:19
1
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When to use IMG vs. CSS background-image?
...ng icon. This ensures that the meaning of the image can be communicated in all user-agents, including screen readers.
Pragmatic uses of IMG
Use IMG plus alt attribute if the image
is part of the content such as a logo or diagram or person (real person, not stock photo people).
—sanchothefat...
Crash logs generated by iPhone Simulator?
...ept trying a few things in the app and it kept crashing). The crashes were all the same, so it wasn't an issue, but I am wondering if this is generally the case?
– Samik R
Dec 8 '12 at 7:46
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CSS technique for a horizontal line with words in the middle
...lign:left; text-indent:40px;" in the h2 style.
– Matt__C
Mar 27 '13 at 21:04
17
This is not flexi...
event Action vs event EventHandler
...u use Action<> your event will not follow the design pattern of virtually any other event in the system, which I would consider a drawback.
One upside with the dominating design pattern (apart from the power of sameness) is that you can extend the EventArgs object with new properties without...