This repository was archived by the owner on Nov 19, 2020. It is now read-only.
ClusterCollection doesn't implement IEnumerable properly (runtime error) #325
Description
Can ClusterCollection be fixed so IEnumerable works as expected?
When you have a cluster collection, e.g.
var clusters = new KMeans(3).Learn(observations);
and you want to iterate through them like this:
foreach (var cluster in clusters) {
// ...
}
You receive the following error:
Exception: System.InvalidCastException: Unable to cast object of type 'SZArrayEnumerator' to type 'System.Collections.Generic.IEnumerator`1[Accord.MachineLearning.KMeansClusterCollection+KMeansCluster]'.
Instead you need to use an old school for loop:
for (int i = 0; i < clusters.Count; i++) {
var cluster = clusters[i];
// ...
}
Can this be fixed?
Test code:
using Accord.MachineLearning;
using System;
// ...
double[][] observations =
{
new double[] { -5, -2, -1 },
new double[] { -5, -5, -6 },
new double[] { 2, 1, 1 },
new double[] { 1, 1, 2 },
new double[] { 1, 2, 2 },
new double[] { 3, 1, 2 },
new double[] { 11, 5, 4 },
new double[] { 15, 5, 6 },
new double[] { 10, 5, 6 },
};
KMeans kmeans = new KMeans(3);
var clusters = kmeans.Learn(observations);
// OK
for (int i = 0; i < clusters.Count; i++) {
var cluster = clusters[i];
Console.WriteLine("Cluster {0}: {1:0.00}%", cluster.Index, cluster.Proportion);
}
// ERROR
foreach (var cluster in clusters) {
Console.WriteLine("Cluster {0}: {1:0.00}%", cluster.Index, cluster.Proportion);
}