Sorting in Chapel

Chapel provides built-in sorting capabilities for arrays and other iterable types. We’ll look at sorting for basic types first.

use Sort;

proc main() {
    // Sorting functions work for any comparable type.
    var strs = ["c", "a", "b"];
    sort(strs);
    writeln("Strings: ", strs);

    // An example of sorting integers.
    var ints = [7, 2, 4];
    sort(ints);
    writeln("Ints:    ", ints);

    // We can also check if an array is already in sorted order.
    var s = isSorted(ints);
    writeln("Sorted:  ", s);
}

To run the program, save it as sorting.chpl and use the Chapel compiler:

$ chpl sorting.chpl -o sorting
$ ./sorting
Strings: a b c
Ints:    2 4 7
Sorted:  true

In this Chapel program:

1. We import the Sort module which provides sorting functions.

2. The sort() function is generic and works for any comparable type. We demonstrate this by sorting an array of strings and an array of integers.

3. Chapel’s arrays are dynamically sized, similar to slices in other languages.

4. The isSorted() function checks if an array is already in sorted order.

5. Chapel uses writeln() for printing to the console, which is similar to println() in other languages.

Note that Chapel’s sorting functions modify the original array in-place, unlike some languages where sorting returns a new sorted array. The sort() function in Chapel is analogous to the slices.Sort() function in the example, providing a simple way to sort arrays of built-in types.

Chapel’s standard modules provide a rich set of algorithms and data structures, making it easy to perform common operations like sorting without having to implement them from scratch.