29 lines
988 B
Matlab
29 lines
988 B
Matlab
function [mu sigma2] = estimateGaussian(X)
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%ESTIMATEGAUSSIAN This function estimates the parameters of a
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%Gaussian distribution using the data in X
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% [mu sigma2] = estimateGaussian(X),
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% The input X is the dataset with each n-dimensional data point in one row
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% The output is an n-dimensional vector mu, the mean of the data set
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% and the variances sigma^2, an n x 1 vector
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%
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% Useful variables
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[m, n] = size(X);
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% You should return these values correctly
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mu = zeros(n, 1);
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sigma2 = zeros(n, 1);
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% ====================== YOUR CODE HERE ======================
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% Instructions: Compute the mean of the data and the variances
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% In particular, mu(i) should contain the mean of
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% the data for the i-th feature and sigma2(i)
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% should contain variance of the i-th feature.
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%
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mu = 1/m * sum(X)';
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sigma2 = 1/m * sum(bsxfun(@minus, X, mu').^2)';
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% =============================================================
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end
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