[regression] first exercise

regression/code/funcPlotter.m

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+function funcPlotter(func)
+  x = 0:0.1:10.0;
+  plot(x,func(x));
+end

regression/code/funcplotterexamples.m

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+funcPlotter(@sin);
+

regression/code/plotlsqcurvefitpower.m

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+meansquarederrorline;               % generate data
+p0 = [2.0, 1.0];
+pest = lsqcurvefit(@powerLaw, p0, x, y)
+
+hold on;
+% generate x-values for plottig the fit:
+xx = min(x):0.01:max(x);
+yy = powerLaw(xx, pest);
+plot(xx, yy);                       % plot fit
+plot(x, y, 'o');                    % plot original data
+xlabel('Size [m]');
+ylabel('Weight [kg]');
+legend('fit', 'data', 'location', 'northwest');

regression/code/powerLaw.m

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+function y = powerLaw(x, p)
+% Power law function y = c*x^alpha.
+%
+% Arguments: x, vector of the x-data values.
+%            p, vector with parameter values c and alpha
+%
+% Returns:   y, vector of the computed y-data values.
+  y = p(1)*x.^p(2);
+end