Problem with DSOLVE (Error using symengine)

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sanderos 2014-8-4

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/145449-problem-with-dsolve-error-using-symengine

评论： sanderos 2014-8-5

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Hey guys, basically I try to translate this maple-code

http://www-personal.umich.edu/~jbarber/elasticity/maple/urt

in matlab. Not so much to change, here the code so far:

function test
syms A rr th nu ff(th) gg(rr)
phi = A*rr^2*log(rr);
srr = simplify((diff(phi, rr))/rr + (diff(phi, th, 2))/rr^2); 
stt = simplify(diff(phi, rr, 2)); 
srt = simplify(-(diff((diff(phi, th))/rr, rr)));
kappa = 3-4*nu;
Epsrr = simplify(((kappa+1)*srr-(3-kappa)*stt)/4);
Epstt = simplify(((kappa+1)*stt-(3-kappa)*srr)/4);
Epsrt = srt;
tmur1 = int(Epsrr, rr);
e1    = rr*Epstt-tmur1;
tmut1 = int(e1, th);
tmur2 = tmur1+diff(ff(th), th);
tmut2 = simplify(tmut1+gg(rr)-ff(th));
hh = simplify(expand(rr*(Epsrt-(1/2)*((1/rr)*diff(tmur2, th) + ...
  diff(tmut2, rr)-tmut2/rr))));
h1 = int(diff(hh), th);
h2 = hh-h1;
sl = dsolve(h1==0);