Radix Sort, Sorting a float data

Is radix sort capable of sorting float开发者_如何学运维 data for example 0.5, 0.9, 1.02, etc.?

Yes, it is possible. It requires an additional pass to correctly handle negative values. The articles by Pierre Terdiman and Michael Herf discuss in detail how to implement it. In short, you convert the float to unsigned integer, sort them, and then convert them back to float (this is required, otherwise the negatives values would be incorrectly sorted after the positive ones).

Their method has the advantage that you do not introduce any error into your data (provided that your processor stores the float in accordance to the IEEE 754 standard).

Not out-of-the-box, but you have some options. You can discretize the data, e.g., by multiplying by 100 and rounding (so that you would have, for your example above, 5, 9, and 102). You could also bucketize the data (grouping numbers by ranges, as in 0 < x <= 1, 1 < x <= 2), and then sort within each bucket.