Question

I’m looking for a data structure which can do search on a specific key. The key is an interval. Once a single value is passed to this structure it should find the correct interval (appropriate key) then this key may point to several other values.

I searched for some key to multiple values and found something like this:

Dictionary<double,LinkedList<T>>

But the key value here is a simple double and is not interval type. And if it was interval type, I must pass the interval as the key. However I need to search based on a single value and find the interval.

In other word, can we have a dictionary-like structure with a custom search behavior? (for example pass the search as an Func<,> parameter.)

Answer 1

I don’t know an existing structure like this. But there are a lot of ways to solve this problem yourself. First thing that comes to mind is to write an extension method for dictionary, like this:

public static class DictionaryRangeExtensions
{
    public IEnumerable<T> FindValuesInRange(this Dictionary<double,T> dictionary, double lowerBound, double upperBound)
    {
         dictionary.Where(kvp=> kvp.Key > lowerBound && kvp.Key < uppoerBound).Select(kvp=>kvp.Value);
    }
}