【mathematica】微分方程求助出现NDSolve::ndsz At t=3.73777385.,step size is effectively zero; singularity or stiff system suspected.是什么意思 应该进行怎样的修改?s = NDSolve[{ D[M1[t], t] == 0.21 q[t] + 3 - M1[t]/(0.5 M1[t]

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【mathematica】微分方程求助出现NDSolve::ndsz At t=3.73777385.,step size is effectively zero; singularity or stiff system suspected.是什么意思 应该进行怎样的修改?s = NDSolve[{ D[M1[t], t] == 0.21 q[t] + 3 - M1[t]/(0.5 M1[t]
【mathematica】微分方程求助
出现NDSolve::ndsz At t=3.73777385.,step size is effectively zero; singularity or stiff system suspected.是什么意思 应该进行怎样的修改?
s = NDSolve[{
D[M1[t], t] == 0.21 q[t] + 3 - M1[t]/(0.5 M1[t] + 0.298 M2[t] + 0.302 M3[t]) 0.5*20,
D[M2[t], t] == 0.44 q[t] - M2[t]/(0.5 M1[t] + 0.298 M2[t] + 0.302 M3[t]) 0.298*20,
D[M3[t], t] == 0.35 q[t] - M3[t]/(0.5 M1[t] + 0.298 M2[t] + 0.302 M3[t]) 0.302*20,
M1[0] == 4, M2[0] == 6, M3[0] == 5.5}, {M1, M2, M3}, {t, 0.01, 9.99}];
Plot[Evaluate[{M1[t], M2[t], M3[t]} /. s], {t, 0, 10}, PlotStyle -> Automatic]

【mathematica】微分方程求助出现NDSolve::ndsz At t=3.73777385.,step size is effectively zero; singularity or stiff system suspected.是什么意思 应该进行怎样的修改?s = NDSolve[{ D[M1[t], t] == 0.21 q[t] + 3 - M1[t]/(0.5 M1[t]
……你不贴代码的话很难判断.这个问题可能在常微分方程及方程组的边值问题求解中出现,解决方法是使用打靶法(具体在帮助里搜搜“打靶法”或者“shooting method"),此外也可能是方程本身的缺陷.总之你最好贴代码.