| 5 | 1/1 | 返回列表 |
| 查看: 1689 | 回復(fù): 6 | |||
| 當(dāng)前只顯示滿足指定條件的回帖,點(diǎn)擊這里查看本話題的所有回帖 | |||
monixia木蟲 (小有名氣)
|
[求助]
求解決matlab解非線性方程組出現(xiàn)的問題 已有1人參與
|
||
|
各位matlab大神,我計(jì)算的方程組如下, >> m=0.00040; f=@(x)([3.14159*m^3+1.9635e-7*x(1)-0.002*3.14159*0.0005^2; 6*(m+x(2))*1.9635e-7-3.14159*m^3+1.9635e-7*x(3)+1.9635e-7*x(6)*(m+x(2))/x(4)-0.002*3.14159*0.0005^2; 3.14159*m^3*x(4)/(m+x(2))+1.9635e-7*x(1)*x(5)/(x(1)+x(3))-1/6*1e-6; (6*1.9635e-7*(m+x(2))-3.14159*m^3)*x(4)/(m+x(2))+1.9635e-7*x(3)*x(5)/(x(1)+x(3))+1.9635e-7*x(6)-1/6*1e-6; fix(0.05/(x(1)+x(3)))*(32*0.0010087*x(5)/0.0005^2*x(3)+7.16*0.07275*(3*(1.0087*x(5)/72.75)^(2/3)/0.0005/(1+3.34*(1.0087*x(5)/72.75)^(2/3))))-6455.68*x(6) 0.05/(m+x(2))*(32*0.0010087*x(4)/0.0005^2*x(2)+7.16*0.07275*(3*(1.0087*x(4)/72.75)^(2/3)/0.0005/(1+3.34*(1.0087*x(4)/72.75)^(2/3))))-6455.68*x(6)]); options = optimset('MaxIter',1e30,'MaxFunEvals',1e50,'TolFun',1e-50); x=fsolve(f,[0.005 0.0005 0.001 0.15 0.9 0.3],options) No solution found. fsolve stopped because the relative size of the current step is less than the default value of the step size tolerance squared, but the vector of function values is not near zero as measured by the selected value of the function tolerance. <stopping criteria details> x = 0.0070 -0.0001 0.0030 0.0344 1.0563 0.4352 fsolve stopped because the relative norm of the current step, 2.848645e-15, is less than max(options.TolX^2,eps) = 1.000000e-12. However, the sum of squared function values, r = 3.833839e-15, exceeds sqrt(options.TolFun) = 1.000000e-25. Optimization Metric Options relative norm(step) = 2.85e-15 max(TolX^2,eps) = 1e-12 (default) r = 3.83e-15 sqrt(TolFun) = 1.0e-25 (selected) 如上,初值已經(jīng)取的很接近實(shí)驗(yàn)值了,還是沒有滿意的結(jié)果。將matlab算的帶入六個(gè)方程, ans = 4.7168e-12 ans = -8.4160e-11 ans = 1.5716e-09 ans = -1.5222e-09 ans = 15.7955 ans = 232.7567 后兩項(xiàng)收斂不是很好。我已經(jīng)嘗試把optimset調(diào)到很小了,可是還是沒有滿意的結(jié)果。 求助各位大牛,這個(gè)該怎么解?還是方程需要修改? 如果圓滿解決,可以加金幣~ |
主管區(qū)長 (職業(yè)作家)
![]() |
專家經(jīng)驗(yàn): +1059 |

主管區(qū)長 (職業(yè)作家)
![]() |
專家經(jīng)驗(yàn): +1059 |

木蟲 (小有名氣)
主管區(qū)長 (職業(yè)作家)
![]() |
專家經(jīng)驗(yàn): +1059 |

| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 297求調(diào)劑 +10 | 田洪有 2026-03-26 | 10/500 |
|
|---|---|---|---|---|
|
[考研] 一志愿雙一流機(jī)械285分求調(diào)劑 +3 | 幸運(yùn)的三木 2026-03-29 | 4/200 |
|
|
[碩博家園] 招收生物學(xué)/細(xì)胞生物學(xué)調(diào)劑 +4 | IceGuo 2026-03-26 | 5/250 |
|
|
[考研] 求調(diào)劑 +7 | 爭(zhēng)取九點(diǎn)睡 2026-03-28 | 8/400 |
|
|
[考研] 085602 化工專碩 338分 求調(diào)劑 +12 | 路癡小琪 2026-03-27 | 12/600 |
|
|
[考研] 0703本科鄭州大學(xué)求調(diào)劑 +3 | nhj_ 2026-03-25 | 3/150 |
|
|
[考研] 311求調(diào)劑 +9 | lin0039 2026-03-26 | 9/450 |
|
|
[考研]
|
孅華 2026-03-22 | 17/850 |
|
|
[考研] 328求調(diào)劑 +7 | 嗯滴的基本都 2026-03-27 | 7/350 |
|
|
[考研] 265求調(diào)劑11408 +3 | 劉小鹿lu 2026-03-27 | 3/150 |
|
|
[考研] 一志愿華東理工大學(xué)081700,初試分?jǐn)?shù)271 +6 | kotoko_ik 2026-03-23 | 7/350 |
|
|
[考研] 求調(diào)劑 +3 | 劉柯@ 2026-03-24 | 4/200 |
|
|
[考研] 一志愿鄭大085600,310分求調(diào)劑 +5 | 李瀟可 2026-03-26 | 5/250 |
|
|
[考研] 359求調(diào)劑 +4 | 王了個(gè)楠 2026-03-25 | 4/200 |
|
|
[考研]
材料學(xué)碩,求調(diào)劑
6+5
|
糖葫蘆888ll 2026-03-22 | 10/500 |
|
|
[考研] 求調(diào)劑 一志愿 本科 北科大 化學(xué) 343 +6 | 13831862839 2026-03-24 | 7/350 |
|
|
[考研] 281求調(diào)劑 +3 | 亞克西good 2026-03-26 | 5/250 |
|
|
[考研] 263求調(diào)劑 +6 | yqdszhdap- 2026-03-22 | 10/500 |
|
|
[考研] 材料與化工328分調(diào)劑 +6 | 。,。,。,。i 2026-03-23 | 6/300 |
|
|
[考研] 石河子大學(xué)(211、雙一流)碩博研究生長期招生公告 +3 | 李子目 2026-03-22 | 3/150 |
|