public ulong knn(
DenseColumnMajorMatrixStorage <float> query,
DenseColumnMajorMatrixStorage <float> indices,//int
DenseColumnMajorMatrixStorage <float> dists2,
Vector <float> maxRadii,
int k,
float epsilon,
SearchOptionFlags optionFlags)
{
checkSizesKnn(query, indices, dists2, k, optionFlags, maxRadii);
bool allowSelfMatch = optionFlags.HasFlag(SearchOptionFlags.AllowSelfMatch);
//bool sortResults = optionFlags.HasFlag(SearchOptionFlags.SortResults);
float maxError2 = ((1 + epsilon) * (1 + epsilon));
Debug.Assert(nodes.Count > 0);
ulong leafTouchedCount = 0;
var off = new float[this.dimensions];
// TODO: Parallel.for?
for (int i = 0; i < query.ColumnCount; ++i)
{
var heap = new ListPriorityQueue <BucketEntry>(k);
float maxRadius = maxRadii[i];
float maxRadius2 = maxRadius * maxRadius;
leafTouchedCount += onePointKnn(query, indices, dists2, i, heap, off, maxError2, maxRadius2, allowSelfMatch);
}
return(leafTouchedCount);
}
public ulong knn(
DenseColumnMajorMatrixStorage <float> query,
DenseColumnMajorMatrixStorage <int> indices,
DenseColumnMajorMatrixStorage <float> dists2,
Vector <float> maxRadii,
int k,
float epsilon,
SearchOptionFlags optionFlags)
{
for (int i = 0; i < query.ColumnCount; i++)
{
onePointKnn(query, i, indices, dists2, maxRadii, k, epsilon, optionFlags);
}
return(0);
}
private ulong onePointKnn(
DenseColumnMajorMatrixStorage <float> query,
int i,
DenseColumnMajorMatrixStorage <int> indices,
DenseColumnMajorMatrixStorage <float> dists2,
Vector <float> maxRadii,
int k,
float epsilon,
SearchOptionFlags optionFlags)
{
var results = new ListPriorityQueue <int>(maxSize: k);
var queryMatrix = new MathNet.Numerics.LinearAlgebra.Single.DenseMatrix(query);
var q = queryMatrix.Column(i);
for (int j = 0; j < cloud.ColumnCount; j++)
{
var c = cloud.Column(j);
var diff = (c - q);
float l2 = diff * diff;
results.Enqueue(j, l2);
}
int kIdx = 0;
foreach (var j in results.Items)
{
indices.At(kIdx, i, j);
kIdx++;
}
kIdx = 0;
foreach (var d2 in results.Priorities)
{
dists2.At(kIdx, i, d2);
}
return(0);
}
private void checkSizesKnn(
DenseColumnMajorMatrixStorage <float> query,
DenseColumnMajorMatrixStorage <float> indices, //int
DenseColumnMajorMatrixStorage <float> dists2,
int k,
SearchOptionFlags optionFlags,
Vector <float> maxRadii)
{
if (k > cloud.ColumnCount)
{
throw new ArgumentException(string.Format("Requesting more points (%1%) than available in cloud (%2%)", k, cloud.ColumnCount));
}
if (query.RowCount < this.dimensions)
{
throw new ArgumentException(string.Format("Query has less dimensions (%1%) than requested for cloud (%2%)", query.RowCount, this.dimensions));
}
if (indices.RowCount != k)
{
throw new ArgumentException(string.Format("Index matrix has a different number of rows (%1%) than k (%2%)", indices.RowCount, k));
}
if (indices.ColumnCount != query.ColumnCount)
{
throw new ArgumentException(string.Format("Index matrix has a different number of columns (%1%) than query (%2%)", indices.ColumnCount, query.ColumnCount));
}
if (dists2.RowCount != k)
{
throw new ArgumentException(string.Format("Distance matrix has a different number of rows (%1%) than k (%2%)", dists2.RowCount, k));
}
if (dists2.ColumnCount != query.ColumnCount)
{
throw new ArgumentException(string.Format("Distance matrix has a different number of columns (%1%) than query (%2%)", dists2.RowCount, query.ColumnCount));
}
if (maxRadii != null && (maxRadii.Count != query.ColumnCount))
{
throw new ArgumentException(string.Format("Maximum radii vector has not the same length (%1%) than query has columns (%2%)", maxRadii.Count, k));
}
}