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Member of the approximation class.

Syntax

coefs = fit(xdata, ydata, model)

[coefs, bestfit] = fit(xdata, ydata, model)

[coefs, bestfit, residue] = fit(xdata, ydata, model)

Description

Computes the coefficients for a curve fitting model.

Examples

Inputs

Name	Description
xdata	Specifies the independent values. xdata is a real, double-precision vector.
ydata	Specifies the dependent values. ydata is a real, double-precision vector.
model	Specifies the fitting model. model is a string that accepts the following values. 'exp1' Specifies an exponential fit. 'linear' Specifies a linear fit. 'polyn' Specifies a polynomial fit of order n. 'power1' Specifies a power fit.

Outputs

Name	Description
coefs	Returns the coefficients of the fit for a model. If model is polyn, coefs returns the coefficients in decreasing order of power. If model is linear, coefs returns the slope and intercept of the linear fit. If model is exp1, coefs returns the amplitude and damping of the exponential fit. If model is power1, coefs returns the power and amplitude of the power fit. coefs is a real, double-precision vector.
bestfit	Returns the values of the fitted curve evaluated at the points in xdata. bestfit is a real, double-precision vector.
residue	Returns the residue of the fitted curve. residue is a real, double-precision scalar.

Examples

XDATA = 1:0.1:10;
YDATA = 1.532*XDATA.^3-0.001*XDATA.^2+4*XDATA-1;
COEFS = fit(XDATA, YDATA, 'poly3');