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countEachLabel

countEachLabel is a function which counts files in ImageDatastore labels. 
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ImageDatastore

ImageDatastore is a useful function and can get a collection of image files, where each individual image fits in memory, but the entire collection of images does not necessarily fit.

Plot a Sinusoidal Wave in Matlab

In this example, we use sinusoidal wave and plot data several different figure.

Use offline WFDB Toolbox for MATLAB

The WFDB Toolbox for MATLAB and Octave is a collection of functions for reading, writing, and processing physiologic signals and time series in the formats used by PhysioBank databases (among others). The Toolbox is compatible with 64-bit MATLAB and GNU Octave on GNU/Linux, Mac OS X, and MS-Windows. To quick start to use offline WFDB Toolbox for Matlab http://physionet.org/physiotools/matlab/wfdb-app-matlab/wfdb-app-toolbox-0-9-6-1.zip  download this file.  Unzip file where you want. When unzip the file, mcode folder will create.  Open MATLAB.  Go where you unzip the file.  Write command line addpath(pwd) Finally write command line again savepath  You can use WFDB Toolbox offline anymore.  [tm,sig]=rdsamp('mitdb/100',1); plot(tm,sig);

Use PCA in Machine Learning

Matlab Code % Source % http://www.dcs.gla.ac.uk/~srogers/firstcourseml/matlab/chapter7/pcaexample.html#2 clear all;close all; % Generate the data Y = [randn(20,2);randn(20,2)+5;randn(20,2)-5]; % Add 5 random dimensions N = size(Y,1); Y = [Y randn(N,5)];

Using PCA on Three Dimensional Dataset

In this work, We use PCA three dimensional data.  Matlab Code % PCA Model clear all, clc , close all hold on axis equal axis([-2 2 -2 2 -2 2]) % Step 1: Get some data X = [1 2 -1 -2 0; 0.2 0 0.1 0.2 -0.4; 1.2 0.3 -1 -0.1 -0.4]'; % Step 2: Substract the mean plot3(X(:,1),X(:,2),X(:,3),'ko'); XAdjust = X-repmat(mean(X),size(X,1),1); plot3(XAdjust(:,1),XAdjust(:,2),XAdjust(:,3),'ro'); % Step 3: Calculate the covariance matrix CM = cov(X); % Step 4: Eigenvalue and Eigenvector [V D]= eig(CM); % Step 5: Choosing component f1 = V(:,1)'; f2 = V(:,2)'; f3 = V(:,3)'; F=[f1; f2; f3];