Cursera: machine learning ex5.

machine_learning/mlclass-ex5-008/mlclass-ex5/polyFeatures.m

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+function [X_poly] = polyFeatures(X, p)
+%POLYFEATURES Maps X (1D vector) into the p-th power
+%   [X_poly] = POLYFEATURES(X, p) takes a data matrix X (size m x 1) and
+%   maps each example into its polynomial features where
+%   X_poly(i, :) = [X(i) X(i).^2 X(i).^3 ...  X(i).^p];
+%
+
+
+% You need to return the following variables correctly.
+X_poly = zeros(numel(X), p);
+
+% ====================== YOUR CODE HERE ======================
+% Instructions: Given a vector X, return a matrix X_poly where the p-th 
+%               column of X contains the values of X to the p-th power.
+%
+% 
+
+X_poly(:,1) = X; 
+for i = 2:p
+	X_poly(:,i) = X_poly(:,i-1).*X;
+end
+
+
+% =========================================================================
+
+end