有六列数据，之间有相互关系，拟合关系为 **y=a1*x1+a2*x2+a3*x3+a4*x4+a5/x5+a6**
  b=xlsread('data1.1.xlsx');
  y=b(:,6);
  x = b(:,1:5);
  beta0=[1 1 1 1 1 1]';
  fun=@(beta,x)x(:,1)*beta(1)+x(:,2)*beta(2)+x(:,3)*beta(3)+x(:,4)*beta(4)+(1./x(:,5))*beta(5)+beta(6);
  [beta,r,J]=nlinfit(x,y,fun,beta0)

  coef0=ones(1,8);
  %fun=@(coef,x_v)(coef(1)*x_v(:,1)+coef(2)*x_v(:,2)+coef(3)*x_v(:,3)+coef(4))/(coef(5)*x_v(:,1)+coef(6)*x_v(:,2)+coef(7)*x_v(:,3)+coef(8));
  x=[[-89.39151256059473,-137.02560212717475,294.21474132740184];
  [-89.00640294668285,-136.43527900566508,292.94722809047147];
  [-92.13506447504953,-141.23111160203118,303.2446077398585];
  [-88.62171346838292,-135.845599897592,291.6810976480241];
  [-90.46633114139622,-138.67315969716176,297.75229720565187];
  [-88.2863231752905,-135.33149005044686,290.5772258653532];
  [-93.44596784537251,-143.2405565538356,307.5591906902628];
  [-90.22568043395219,-138.3042733549881,296.96024230454583];
  [-89.2790025102939,-136.85313880323915,293.84443642486923];
  [-94.15101574482283,-144.32130359774754,309.8797184385722];
  [-95.83952722105414,-146.9095728316125,315.43712487434533];
  [-88.91364351681958,-136.29309082285104,292.6419285057441];
  [-86.79813484746683,-133.0502902378758,285.67914402989595];
  [-92.65651132990632,-142.0304220423332,304.9608484334443];
  [-91.38782426489834,-140.08568921464072,300.78521222409256]];
  phi=[-89.39151256059473;
  -89.00640294668285;
  -92.13506447504953;
  -88.62171346838292;
  -90.46633114139622;
  -88.2863231752905;
  -93.44596784537251;
  -90.22568043395219;
  -89.2790025102939;
  -94.15101574482283;
  -95.83952722105414;
  -88.91364351681958;
  -86.79813484746683;
  -92.65651132990632;
  -91.38782426489834];
  %testf(coef,[2,3,3])
  coef=nlinfit(x,phi,testf,coef0);
  %coef=lsqnonlin('x,phi',coef0,x,phi);