Hi,

I have a set of data and I need to calculate the trigonometric curve by using the "curve fitting tool" of Matlab.

The curve is computed regularly and the plot on the tool fit all the point, but the function doesn't fit anyone point of the set, it seems out of scale.

Thanks in advance.

Point set

`x1= [0.072553;0.773202;1.378368;1.788931;2.450787;3.010140;3.447557;3.837764;4.187158;4.460306;4.635640;4.712404;4.719292;4.719436]z1 =[ 4.854458;4.770619;4.706262;4.620619;4.270619;3.770619;3.270619;2.770619;2.270619;1.770619;1.270619;0.770619;0.268003;0.000000]`

`the output of the Fourier's series is:General model Fourier2: f(x) = a0 + a1*cos(x*w) + b1*sin(x*w) + a2*cos(2*x*w) + b2*sin(2*x*w)Coefficients (with 95% confidence bounds):`

a0 = -5.229e+07 (-4.405e+12, 4.405e+12) a1 = 6.971e+07 (-5.872e+12, 5.872e+12) b1 = 1.143e+06 (-7.223e+10, 7.223e+10) a2 = -1.742e+07 (-1.468e+12, 1.468e+12) b2 = -5.716e+05 (-3.611e+10, 3.611e+10) w = 0.008349 (-175.8, 175.8)Goodness of fit: SSE: 0.7653 R-square: 0.9811 Adjusted R-square: 0.9692 RMSE: 0.3093

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