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sfit

Constructor for sfit object

Syntax

surfacefit = sfit(fittype,coeff1,coeff2,...)

Description

An sfit object encapsulates the result of fitting a surface to data. They are normally constructed by calling the fit function, or interactively by exporting a fit from the Curve Fitting app to the workspace. You can get and set coefficient properties of the sfit object.

You can treat an sfit object as a function to make predictions or evaluate the surface at values of X and Y.

Like the cfit class, sfit inherits all fittype methods.

surfacefit = sfit(fittype,coeff1,coeff2,...) constructs the sfit object surfacefit using the model type specified by the fittype object and the coefficient values coeff1, coeff2, etc.

    Note:   sfit is called by the fit function when fitting fittype objects to data. To create a sfit object that is the result of a regression, use fit.

    You should only call sfit directly if you want to assign values to coefficients and problem parameters of a fittype object without performing a fit.

Methods of sfit objects:

argnames Input argument names of cfit, sfit, or fittype object
categoryCategory of fit of cfit, sfit, or fittype object
coeffnamesCoefficient names of cfit, sfit, or fittype object
coeffvaluesCoefficient values of cfit or sfit object
confintConfidence intervals for fit coefficients of cfit or sfit object
dependnamesDependent variable of cfit, sfit, or fittype object
differentiateDifferentiate cfit or sfit object
fevalEvaluate cfit, sfit, or fittype object
formulaFormula of cfit, sfit, or fittype object
indepnamesIndependent variable of cfit, sfit, or fittype object
islinearDetermine if cfit, sfit, or fittype object is linear
numargsNumber of input arguments of cfit, sfit, or fittype object
numcoeffsNumber of coefficients of cfit, sfit, or fittype object
plotPlot cfit or sfit object
predintPrediction intervals for cfit or sfit object
probnamesProblem-dependent parameter names of cfit, sfit, or fittype object
probvaluesProblem-dependent parameter values of cfit or sfit object
quad2dNumerically integrate sfit object
setoptions Set model fit options
sfitConstructor for sfit object
typeName of cfit, sfit, or fittype object

Examples

You can treat an sfit object as a function to make predictions or evaluate the surface at values of X and Y, e.g.,

        x = 3 - 6 * rand( 49, 1 );
        y = 3 - 6 * rand( 49, 1 );
        z = peaks( x, y );
        sf = fit( [x, y], z, 'poly32' );
        zhat = sf( mean( x ), mean( y ) )

See Also

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