curvefit.m

matlab7.0从入门到精通(光盘内容)

Function CurveFit(aData, sTarget1, sTarget2, sTarget3)
    'MATLAB regression and curve fitting macro
    
    MLPutMatrix "data", aData
    MLEvalString "y = data(:,3)"
    MLEvalString "n = length(y)"
    MLEvalString "e = ones(n,1)"
    MLEvalString "A = [e data(:,1:2)]"
    MLEvalString "beta = A\y"
    MLEvalString "fit = A*beta"
    MLEvalString "[y,k] = sort(y)"
    MLEvalString "fit = fit(k)"
    MLEvalString "[p,S] = polyfit(1:n,y',5)"
    MLEvalString "newfit = polyval(p,1:n,S)'"
    MLEvalString "plot(1:n,y,'bo',1:n,fit,'r:',1:n,newfit,'g');legend('data','fit','newfit')"
    MLGetMatrix "y", sTarget1
    MLGetMatrix "fit", sTarget2
    MLGetMatrix "newfit", sTarget3
End Function