ndhistogram 0.2.1

multi-dimensional histogramming for Rust
Documentation 
// #[test]
// #[should_panic]
// fn test_histogram_category_grows() {
//     let mut hist = ndhistogram!(Category::growable(vec!["A", "B"]); i32);
//     assert_eq!(hist.value(&"C"), None);
//     hist.fill(&"C");
//     assert_eq!(hist.value(&"C"), Some(&1));
//     // check every bin value
//     let actual: Vec<_> = hist.iter().collect();
//     let expected = vec![
//         Item::new(0, SingleValuedBinInterval::new("A"), &0),
//         Item::new(1, SingleValuedBinInterval::new("B"), &0),
//         Item::new(2, SingleValuedBinInterval::new("C"), &1),
//     ];
//     assert_eq!(expected, actual);
// }