15 lines
487 B
Matlab
15 lines
487 B
Matlab
function dmsedc = meanSquaredGradientCubic(x, y, c)
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% The gradient of the mean squared error for a cubic relation.
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%
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% Arguments: x, vector of the x-data values
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% y, vector of the corresponding y-data values
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% c, the factor for the cubic relation.
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%
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% Returns: the derivative of the mean squared error at c.
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h = 1e-7; % stepsize for derivatives
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mse = meanSquaredErrorCubic(x, y, c);
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mseh = meanSquaredErrorCubic(x, y, c+h);
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dmsedc = (mseh - mse)/h;
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end
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