为什么model:x^2+y^2=2; 2*x^2+x+y^2+y=4; end 在lingo实现时显示错误有个教程上说会得出 Feasible solution found at iteration:0 Variable ValueX 0.4543360Y 1.339247

用lingo解决一个简单的优化问题下面几种写法算出的结果不一样 为什么?min=fx+fy;fx=@if(x#gt#0,100,0)+2*x;fy=@if(y#gt#0,60+y,0)+2*y;x+y>=30;model:min=fx+fy;fx=@if(x #gt# 0,100,0)+2*x;fy=@if(y #gt# 0,60+3*y,2*y);x+y>=30;end lingo解非线性方程组的问题.参考书上写的代码：model:x^2+y^2=2;2*x^2+x+y^2+y=4;end解出结果Feasible solution found at iteration:0Variable ValueX 0.4543360Y 1.339247为什么我用lingo这么做总是出错呢? 为什么model:x^2+y^2=2; 2*x^2+x+y^2+y=4; end 在lingo实现时显示错误有个教程上说会得出 Feasible solution found at iteration:0 Variable ValueX 0.4543360Y 1.339247 lingo菜鸟问题model:x^2+y^2=2;x^2+2*x+y^2+y=4;end的运行结果为什么会有Solution is locally infeasible的提示并且结果会是Variable ValueX 1.414214Y 0.000000显然不是正确的啊问题出在哪里? 关于 LINGO @FOR 语句请问下面的@for 语句中为什么@for(set1(i):@sum(set1(k):x(k))=1); i j k 总是在换啊?model:sets:set1/1..2/:x;set2/1..2/:y;link(set1,set2):a,b;endsets@for(set1(i):@sum(set1(k):x(k))=1);@for(set2(j):@sum(set2(k):y(k)) lingo程序错误1017model:sets:question(/1..i/):x,y;endsetsinit:x(1)=0;y(1)=0;endinit[obj] max=@sum(link(i,j):c(i))@for(question:(min(@sqrt((x(i)-x(i1))^2+(y(i)-y(j))^2))>=z););@for(question:(max(@sqrt((x(i)-x(i1))^2+(y(i)-y(j))^2)) 小弟刚接触LINGO,实在是没辙了,编写完成后出现model is ill difined希望各位好心人帮助,十万火急,谢谢model:sets:DMU/1..14/:H,W;II/1..2/;OI/1..2/; IV(II,DMU):X;OV(OI,DMU):Y; endsetsdata:X=0.37418 0.144448 0.106145 0.122964 2x-5y=0,y/x=为什么 LINGO程序总是有问题model:sets:entrance/1/:x,y;endsetsinit:x=0;y=0;endinit[OBJ]min = ((45-x(i))^2+y(i)^2)^(1/2)+((35-x(i))^2+(100-y(i))^2)^(1/2)+((120-x(i))^2+(100-y(i))^2)^(1/2);((45-x(i))^2+y(i)^2)^(1/2)+((35-x(i))^2+(100-y(i))^2)^(1/2)+30 lingo中不是可以取消变量的非负限制吗,为什么老是出错啊Model:Title Location Problem;sets:demand/1..6/:a,b,d;supply/1..2/:x,y,e;link(demand,supply):c;endsetsdata:a=1.25,8.75,0.5,5.75,3,7.25;b=1.25,0.75,4.75,5,6.5,7.75;d=3,5,4,7,6,1 lingo中不是可以取消变量的非负限制吗,为什么老是出错啊,Model:Title Location Problem;sets:demand/1..6/:a,b,d;supply/1..2/:x,y,e;link(demand,supply):c;endsetsdata:a=1.25,8.75,0.5,5.75,3,7.25;b=1.25,0.75,4.75,5,6.5,7.75;d=3,5,4,7,6, lingo中这个INVALIDSETNAME.错误怎么改model:sets:bzx/1..7/:x,y,t,w,n;endsetsmin=20.4*10^2-@sum(bzx(i):(t(i)*x(i)+t(i)*y(i)));@for(bzx(i):@gin(x(i))); @for(bzx(i):@gin(y(i)));@for( @sum(bzx(i)|i#gt#4:t(i)*x(i)+t(i)*y(i)) line(x,y,x,y 18);onstkey_typedict(model,lo_val,hi_val);for(p=0;p LINGO老是算不出来条件约束求帮忙model:max=v;v=288*pi-2*pi*y*y+1/3*pi*x*y*(12-y);s对了圆球的半径限定为6了，x是圆锥的高，y是圆陷进圆锥的深度 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 为什么(x-2y)(x+4y)-(x-2y)+3(x+4y)-3=(x-2y+3)(x+4y-1). 为什么x=2y!第十题 为什么y=x^2没有反函数?