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[综合讨论] matlab自动关闭问题

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发表于 2007-6-25 11:23 | 显示全部楼层 |阅读模式

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近日在进行比较大的符号运算程序,其中公式可能比较长,但是我尽量拆开简化,最后一部分是解非齐次微分方程,可每次算到一部分就matlab自动关闭,不知道怎么回事
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发表于 2007-6-25 12:49 | 显示全部楼层
问题及处理贴一下.
另: 可以用vpa简化一下表达式试试; 或者改用Mathematica求解.

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 楼主| 发表于 2007-6-25 17:07 | 显示全部楼层
会不会有可能是我的电脑内存不够大,1G的
程序如下
clear all
clc
syms setac c1 c2 c3 c4 c5 d w1 w2 w3 r1 r2 r3 p1 p2 p3 ep t G1 G2 G3 s1 s2 s3 r0 p0
syms a1 a2 a3 a4 a5 b1 b2 b3 b4 b5 k F1 F2 F3 uc A11 A13 A10 A41 A43 A40 A71 A73 A70
F1=-(3*A11*(c1+c2*r1)+3*A13*(c3+c4*r1-c5*p1)+3*A10*(-3*r1*c5+3*p1*c5))/(6*A11+6*r1*A13+3*p1*A10);
G2=-(3*A41*(c1+c2*r2)+3*A43*(c3+c4*r2-c5*p2)+3*A40*(-3*r2*c5+3*p2*c5))/(6*A41+6*r2*A43+3*p2*A40);
G3=-(3*A71*(c1+c2*r3)+3*A73*(c3+c4*r3-c5*p3)+3*A70*(-3*r3*c5+3*p3*c5))/(6*A71+6*r3*A73+3*p3*A70);
H1=-(3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))+3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1;
H2=-(3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))+3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2;
H3=-(3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))+3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3;

ui0=uc+2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
zi0=r0+r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
ur0=p0+p1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +p2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +p3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);

DDui0=-F2*ep*w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
      -H2*ep*w2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
      -F3*ep*w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3) ...
      -H3*ep*w3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
DDzi0=-r2*F2*ep*w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
      -r2*H2*ep*w2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
      -r3*F3*ep*w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3) ...
      -r3*H3*ep*w3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
DDur0=-p2*F2*ep*w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
      -p2*H2*ep*w2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
      -p3*F3*ep*w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3) ...
      -p3*H3*ep*w3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
  
Dui0=-w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
     -w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3);
Dzi0=-r2*w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
     -r3*w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3);
Dur0=-p2*w2*2*G2*exp(F2*ep*t)*sin(w2*t+H2*ep*t+s2) ...
     -p3*w3*2*G3*exp(F3*ep*t)*sin(w3*t+H3*ep*t+s3);

ui2=uc^2+(2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1))^2 ...
    +(2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2))^2 ...
    +(2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3))^2 ...
    +4*uc*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +4*uc*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +8*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +8*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +8*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);

zi2=r0^2+(r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1))^2 ...
    +(r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2))^2 ...
    +(r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3))^2 ...
    +2*r0*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*r0*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);
   
ur2=p0^2+(p1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1))^2 ...
    +(p2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2))^2 ...
    +(p3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3))^2 ...
    +2*p0*p2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*p0*p3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*p1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*p2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*p1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*p3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*p2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*p3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);

sez=uc*r0 ...
    +uc*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +uc*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1)*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*r0 ...
    +2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2)*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3) ...
    +2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3)*r0 ...
    +2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3)*r1*2*G1*exp(F1*ep*t)*cos(w1*t+H1*ep*t+s1) ...
    +2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3)*r2*2*G2*exp(F2*ep*t)*cos(w2*t+H2*ep*t+s2) ...
    +2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3)*r3*2*G3*exp(F3*ep*t)*cos(w3*t+H3*ep*t+s3);

ff11=-2*DDui0;ff12=-c1*Dui0;ff13=-c2*Dzi0;ff14=-a3*ui2;ff15=-a4*zi2;ff16=-a5*sez;
ff21=-2*DDzi0;ff22=-c3*Dui0;ff23=-c4*Dzi0;ff24=-c5*Dur0;ff25=-b3*ui2;ff26=-b4*zi2;ff27=-b5*sez;

ff31=-2*DDur0;ff32=3*c5*Dzi0;ff33=-3*c5*Dur0;



Fn11=-3*0.8787*ff11;Fn12=-3*0.8787*ff12;Fn13=-3*0.8787*ff13;Fn14=-3*0.8787*ff14;Fn15=-3*0.8787*ff15;Fn16=-3*0.8787*ff16;
Fn21=-3*0.1382*ff21;Fn22=-3*0.1382*ff22;Fn23=-3*0.1382*ff23;Fn24=-3*0.1382*ff24;Fn25=-3*0.1382*ff25;
Fn26=-3*0.1382*ff26;Fn27=-3*0.1382*ff27;
Fn31=-0.2097*ff31;Fn32=-0.2097*ff32;Fn33=-0.2097*ff33;


f1=dsolve('D2x+w1^2*x-(26361/10000*a5*(uc*r0+2*uc*r2*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)+2*uc*r3*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)+4*G1^2*exp((-3*A11*(c1+c2*r1)-3*A13*(c3+c4*r1-c5*p1)-3*A10*(-3*r1*c5+3*c5*p1))/(6*A11+6*r1*A13+3*p1*A10)*ep*t)^2*cos(w1*t+(-3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))-3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1*ep*t+s1)^2*r1+4*G1*exp((-3*A11*(c1+c2*r1)-3*A13*(c3+c4*r1-c5*p1)-3*A10*(-3*r1*c5+3*c5*p1))/(6*A11+6*r1*A13+3*p1*A10)*ep*t)*cos(w1*t+(-3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))-3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1*ep*t+s1)*r2*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)+4*G1*exp((-3*A11*(c1+c2*r1)-3*A13*(c3+c4*r1-c5*p1)-3*A10*(-3*r1*c5+3*c5*p1))/(6*A11+6*r1*A13+3*p1*A10)*ep*t)*cos(w1*t+(-3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))-3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1*ep*t+s1)*r3*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)+2*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)*r0+4*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)*r1*G1*exp((-3*A11*(c1+c2*r1)-3*A13*(c3+c4*r1-c5*p1)-3*A10*(-3*r1*c5+3*c5*p1))/(6*A11+6*r1*A13+3*p1*A10)*ep*t)*cos(w1*t+(-3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))-3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1*ep*t+s1)+4*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))^2/(6*A41+6*r2*A43+3*p2*A40)^2*exp(F2*ep*t)^2*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)^2*r2+4*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)*r3*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)+2*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)*r0+4*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)*r1*G1*exp((-3*A11*(c1+c2*r1)-3*A13*(c3+c4*r1-c5*p1)-3*A10*(-3*r1*c5+3*c5*p1))/(6*A11+6*r1*A13+3*p1*A10)*ep*t)*cos(w1*t+(-3*A11*(2*a3*uc+2*a4*r0*r1+a5*(uc*r1+r0))-3*A13*(2*b3*uc+2*b4*r0*r1+b5*(uc*r1+r0)))/(6*A11+6*r1*A13+3*p1*A10)/w1*ep*t+s1)+4*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))/(6*A71+6*r3*A73+3*p3*A70)*exp(F3*ep*t)*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)*r2*(-3*A41*(c1+c2*r2)-3*A43*(c3+c4*r2-c5*p2)-3*A40*(-3*r2*c5+3*c5*p2))/(6*A41+6*r2*A43+3*p2*A40)*exp(F2*ep*t)*cos(w2*t+(-3*A41*(2*a3*uc+2*a4*r0*r2+a5*(uc*r2+r0))-3*A43*(2*b3*uc+2*b4*r0*r2+b5*(uc*r2+r0)))/(6*A41+6*r2*A43+3*p2*A40)/w2*ep*t+s2)+4*(-3*A71*(c1+c2*r3)-3*A73*(c3+c4*r3-c5*p3)-3*A70*(-3*r3*c5+3*c5*p3))^2/(6*A71+6*r3*A73+3*p3*A70)^2*exp(F3*ep*t)^2*cos(w3*t+(-3*A71*(2*a3*uc+2*a4*r0*r3+a5*(uc*r3+r0))-3*A73*(2*b3*uc+2*b4*r0*r3+b5*(uc*r3+r0)))/(6*A71+6*r3*A73+3*p3*A70)/w3*ep*t+s3)^2*r3))=0','t');
 楼主| 发表于 2007-6-25 17:07 | 显示全部楼层
后面那个解微分方程实在是有点长,我正在努力化简
发表于 2007-6-25 18:49 | 显示全部楼层
1G 比较大了
我的还是256M的。
这个方程确实比较大,还有一个问题,你用dsolve求解的精度满足你的计算要求吗?怎么去控制的。因为我原来做的时候经常遇到精度和初值的问题!
 楼主| 发表于 2007-6-25 19:01 | 显示全部楼层
初值我现在没有考虑,因为我要解析解,然后这个还需要带入其他条件中来求解特解
 楼主| 发表于 2007-6-25 19:51 | 显示全部楼层
我有简化了一下,可以算出来了,但是具体为什么matlab自动关闭还是不知道为什么
发表于 2007-6-25 23:17 | 显示全部楼层
看了一下,这种问题,这么多符号变量,用Matlab能算出解析解来也算是半个奇迹了。:@o
用Mathematica会更合适一些.
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