[lincsu]

coeff是所求的未知系数，一共三个参数
xdata=【0：0.001：3】。。。。1x3001
ydata=不规则的数据，请见附件,长度1x3001
是一个公式求出来的数值
附件是matlab中.mat文件，下载后可以改成.mat后缀

求解的曲线是：
F=coeff(3)^2./((coeff(2)-xdata.^2).^2+(coeff(1)*xdata).^2);

非常感谢，我使用了：
coeff0 = [5; 8; 0.00001]; % Starting guess
[coeff,resnorm] = lsqcurvefit(@myfun,coeff0,xdata,ydata)

function F = myfun(coeff,xdata)
F=coeff(3)^2./((coeff(2)-xdata.^2).^2+(coeff(1)*xdata).^2);

但是一直出错：
??? Error using ==> optim\private\snls at 304
lsqcurvefit cannot continue: user function is returning Inf or NaN values.

Error in ==> optim\private\lsqncommon at 221
[x,FVAL,LAMBDA,JACOB,EXITFLAG,OUTPUT,msg]=...

Error in ==> lsqcurvefit at 182
[x,Resnorm,FVAL,EXITFLAG,OUTPUT,LAMBDA,JACOB] = ...

Error in ==> white_noise_to_color at 25
[coeff,resnorm] = lsqcurvefit(@myfun,coeff0,omega,S_FF)