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Why doesn’t the array class have a .sort()? I don't know how to sort an array directly.

The class array.array is a packed list which looks like a C array. I want to use it because only numbers are needed in my case, but I need to be able to sort it. Is there some way to do that efficiently?

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  • Maybe numpy is appropriate? stackoverflow.com/questions/5540148/… Commented Feb 5, 2017 at 1:56
  • @Ryan it't a good idea,but I still wonder why array.array() hasn't .sort(), Commented Feb 7, 2017 at 12:09
  • @Ryan , an array which can compactly represent an array of basic values, that means no py_object,just new int[],short[] or something else,it can be fast.if you want sort,just call qsort() in C. so I'm ……confused Commented Feb 7, 2017 at 12:22
  • Yeah, I don’t know why it doesn’t. Commented Feb 7, 2017 at 12:39

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I cannot see a justification why this is missing, and this is really against the batteries included philosophy of Python. A sort function with a key argument would be really helpful to sort arrays of indices pointing to something else.

To sort an array a you could of course do:

a = array.array("L", sorted(a))

but that would not be in place and would cost quite some memory and runtime, converting the array to a list and back to an array.

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A list is a data structure that has characteristics which make it easy to do some things. An array is a very well understood standard data structure and isn't optimized for sorting. An array is basically a standard way of storing the product of sets of data. There hasn't ever been a notion of sorting it.

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“A list is a data structure that has characteristics which make it easy to do some things.” That’s not very specific. “An array is a very well understood standard data structure and isn't optimized for sorting.” What. “An array is basically a standard way of storing the product of sets of data. There hasn't ever been a notion of sorting it.” What.
I thank you for the first bit as it is constructive. However I'm afraid you'll have to be more specific for the second complaint. An array is a standard data structure.
Specifically: “isn’t optimized for sorting” was the part I took issue with. There are tons of algorithms for sorting sequences with constant-time random read and write, i.e. arrays. Maybe you’re talking about a different kind of array with a definition closer to “a standard way of storing the product of sets of data”? array.array (what the question seems to be about) is just a packed list, though.
But again an array is a standard variable that takes an natural number or Cartesian product of them and out puts or maps to a some other object. Any implementation typically must produce this functionality to be what we think of when we think "array". Nothing further is required.
"An array is basically a standard way of storing the product of sets of data." Nope. Thats plain wrong. An array in python is a linear sequence of integer values allowing constant time random access. This has nothing to do with products or sets or Cartesian products.
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