private int GetPartitionIndexFromIteration(BigInteger iteration)
{
var count = Count;
if (iteration >= count)
{
throw new IndexOutOfRangeException($"Index out of range! Select between 0 and {count}");
}
// Lets say total count is 8007 words from 8 partitions.
// Part[0-6] is 1k words and Part[7] is 1007 words.
// Iteration is 3003, return partition index 3.
var minRange = 0;
var maxRange = PartitionedWords.First().Count;
int partitionIndex;
for (partitionIndex = 1; partitionIndex < PartitionedWords.Count; partitionIndex++)
{
minRange += PartitionedWords.ElementAt(partitionIndex).Count;
if (minRange < iteration && iteration < maxRange)
{
return(partitionIndex);
}
maxRange += minRange;
}
return(-1);
}
/// <summary>
/// Returns a specific partition of words given the partition index.
/// </summary>
/// <param name="partitionIndex">The index of the parent collection.</param>
/// <returns>A specific partition </returns>
/// <exception cref="PartitionIndexOutOfRange">Thrown if the partitionIndex is out of range.</exception>
public IDictionary <int, IGeneratedWord> GetWordsAtIndex(int partitionIndex)
{
var count = PartitionedWords.Count();
var emptyWordSet = new ConcurrentDictionary <int, IGeneratedWord>();
if (partitionIndex < 0 || partitionIndex >= count)
{
throw new PartitionIndexOutOfRange(partitionIndex, nameof(partitionIndex));
}
return(PartitionedWords.ElementAt(partitionIndex));
}