function obj=lsqfun3(t12,t21,t13,t31,t23,t32)

%t12,t21,t13,t31,t23,t32，是所需要关联的NRTL方程参数；

%a1,a2,a3,是组分1,2,3，液相平衡数据；

%y1,y2,y3,是组分1,2,3，气相平衡数据；

%ps1，ps2，ps3，是组分1,2,3的饱和蒸汽压；

%p==101.35;

%obj为

p=101.35;

y1=[];

y2=[];

y3=[];

a1=[];

a2=[];

a3=[];

ps1=[];

ps2=[];

ps3=[];

k1=(a2.^2*t21*exp(-0.3*t21)^2+a3.^2*t31*exp(-0.3*t31)*exp(-0.3*t31)+a2.*a3*exp(-0.3*t21)*exp(-0.3*t31)*(t21+t31))./((a1+a2.*exp(-0.3*t21)+a3*exp(-0.3*t31)).^2);

k2=(a2.^2*t12*exp(-0.3*t12)+a2.*a3*exp(-0.3*t12)*exp(-0.3*t32)*(t12-t32))./((a1*exp(-0.3*t12)+a2+a3*exp(-0.3*t32)).^2);

k3=(a3.^2*t13*exp(-0.3*t13)+a2.*a3*exp(-0.3*t13)*exp(-0.3*t23)*(t13-t23))./((a1*exp(-0.3*t13)+a2*exp(-0.3*t23)+a3).^2);

k4=(a1.^2*t21*exp(-0.3*t21)+a1.*a3*exp(-0.3*t21)*exp(-0.3*t31)*(t21-t31))./((a1+a2*exp(-0.3*t21)+a3*exp(-0.3*t31)).^2);

k5=(a1.^2*t12*exp(-0.3*t12)^2+a3.^2*t32*exp(-0.3*t32)^2+a1.*a3*exp(-0.3*t12)*exp(-0.3*t32)*(t12+t32))./((a1*exp(-0.3*t12)+a2+a3*exp(-0.3*t32)).^2);

k6=(a3.^2*t23*exp(-0.3*t23)+a1.*a3*exp(-0.3*t13)*exp(-0.3*t23)*(t23-t13))./((a1*exp(-0.3*t13)+a2*exp(-0.3*t23)+a3).^2);

k7=(a1.^2*t31*exp(-0.3*t31)+a1.*a2*exp(-0.3*t21)*exp(-0.3*t31)*(t31-t21))./((a1+a2*exp(-0.3*t21)+a3*exp(-0.3*t31)).^2);

k8=(a2.^2*t32*exp(-0.3*t32)^2+a1.*a2*exp(-0.3*t12)*exp(-0.3*t32)*(t32-t12))./((a1*exp(-0.3*t12)+a2+a3*exp(-0.3*t32)).^2);

k9=(a1.^2*t13*exp(-0.3*t13)^2+a2.^2*t23*exp(-0.3*t23)^2+a1.*a2*exp(-0.3*t13)*exp(-0.3*t23)*(t13+t23))./((a1*exp(-0.3*t13)+a2*exp(-0.3*t23)+a3).^2);

gama1=exp(k1+k2+k3);

gama2=exp(k4+k5+k6);

gama3=exp(k7+k8+k9);

y1c=ps1.*gama1.*a1./p;

y2c=ps2*gama2*a2./p;

y3c=ps3*gama3*a3./p;

obj=sum(sum((y1c-y1).^2+(y2c-y2).^2+(y3c-y3).^2));