k-Nearest Neighbors (kNN) Classifier

Multi-class Classification with the kNN
2.1K Downloads
Updated Wed, 28 Oct 2020 05:52:05 +0000

Function
1. kNNeighbors.predict(_)
2. kNNeighbors.find(_)

Description
1. Returns the estimated labels of one or multiple test instances.
2. Returns the indices and the respective distances of the k nearest training instances.

Examples using Iris Data Set

load fisheriris

X = meas;
Y = species;
Xnew = [min(X);mean(X);max(X)];
k = 5;
metric = 'euclidean';

mdl = kNNeighbors(k,metric);
mdl = mdl.fit(X,Y);
Ypred = mdl.predict(Xnew)

Ypred =

'setosa'
'versicolor'
'virginica'


Ynew = {'versicolor';'versicolor';'virginica'};
accuracy = accuracy_score(Ypred,Ynew)

accuracy =

0.6667

See examples in the script files.

Cite As

David Ferreira (2019). k-Nearest Neighbors (kNN) (https://www.mathworks.com/matlabcentral/fileexchange/67018-k-nearest-neighbors-knn), MathWorks. Retrieved January 23, 2019.

MATLAB Release Compatibility
Created with R2016a
Compatible with any release
Platform Compatibility
Windows macOS Linux
Categories
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Versions that use the GitHub default branch cannot be downloaded

Version Published Release Notes
2.2.1

See release notes for this release on GitHub: https://github.com/ferreirad08/kNNeighborsClassifier/releases/tag/2.2.1

2.2.0

See release notes for this release on GitHub: https://github.com/ferreirad08/k-Nearest-Neighbors-kNN-Algorithm/releases/tag/2.2.0

2.1.9

See release notes for this release on GitHub: https://github.com/ferreirad08/k-Nearest-Neighbors-kNN-Algorithm/releases/tag/2.1.9

2.1.8

Find function added

2.1.7

Description correction

2.1.6

Description correction

2.1.5

Description correction

2.1.4

Description correction

2.1.3

3-D chart added and cell type label support.

2.1.2

The plotting 3-D function was added in the main algorithm.

2.1.1

More markers were added to the chart.

2.1.0

The plotting function was added in the main algorithm.

2.0.9

Function Pack

2.0.8

Title correction

2.0.7

Title correction

2.0.6

Added to github.

2.0.5

New tools have been added, bringing a more complete algorithm.

2.0.4

Simplification in k nearest instances and k nearest labels

2.0.3

Basic update

2.0.2

Update in maximum frequency

2.0.1

Simplification in frequency verification

2.0.0

Check the frequencies using 'histcounts'

1.62

Title correction

1.61

Correction of the k nearest labels.

1.60

Returns the k nearest labels.

1.54

Basic update

1.53

Updating the Euclidean distance between two points

1.52

Description correction

1.51

Description correction

1.5

Elements sorted by "sort" function and reduced processing time by approximately 1/3.

1.1.0.0

Update of the calculation of the Euclidean distance between two points

1.0.0.0

Description correction
It was added the verification of the dimensions of the matrices.

To view or report issues in this GitHub add-on, visit the GitHub Repository.
To view or report issues in this GitHub add-on, visit the GitHub Repository.