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# nearestNeighbor

Class: DelaunayTri

(Will be removed) Point closest to specified location

 Note:   nearestNeighbor(DelaunayTri) will be removed in a future release. Use nearestNeighbor(delaunayTriangulation) instead.DelaunayTri will be removed in a future release. Use delaunayTriangulation instead.

## Syntax

PI = nearestNeighbor(DT,QX)
PI = nearestNeighbor(DT,QX,QY)
PI = nearestNeighbor(DT,QX,QY,QZ)
[PI,D] = nearestNeighbor(DT,QX,...)

## Description

PI = nearestNeighbor(DT,QX) returns the index of the nearest point in DT.X for each query point location in QX.

PI = nearestNeighbor(DT,QX,QY) and PI = nearestNeighbor(DT,QX,QY,QZ) allow the query points to be specified in column vector format when working in 2-D and 3-D.

[PI,D] = nearestNeighbor(DT,QX,...) returns the index of the nearest point in DT.X for each query point location in QX. The corresponding Euclidean distances between the query points and their nearest neighbors are returned in D.

 Note:   Note: nearestNeighbor is not supported for 2-D triangulations that have constrained edges.

## Input Arguments

 DT Delaunay triangulation. QX The matrix QX is of size mpts-by-ndim, mpts being the number of query points and ndim the dimension of the space where the points reside.

## Output Arguments

 PI PI is a column vector of point indices that index into the points DT.X. The length of PI is equal to the number of query points mpts D D is a column vector of length mpts.

## Examples

Create a Delaunay triangulation:

```x = rand(10,1);
y = rand(10,1);
dt = DelaunayTri(x,y);```

Create query points:

`qrypts = [0.25 0.25; 0.5 0.5];`

Find the nearest neighbors to the query points:

`pid = nearestNeighbor(dt, qrypts)`