小第用mathematical编了一个程序，但老出错，请各位大虾指点
Clear[QF1, QF2, ma, mb, a, b, ω, t, ka, kb, ca, cb, k, Ee,Ii]
LagrangianEquations[T_, V_, Q_List,
Coor_List] := Module[{L = T - V}, MapThread[∂\_t\ \((
∂\_\(∂\_t\ #2\)\ L)\) - ∂\_#2\ L == #1 &, {Q, Coor}]]
Coords = {\((q)\), \((q)\), qa, qb}\)
ma = 0.1910507304
mb = 0.0120078892
ρ = 0.00304
A = 5.25
L = 50.0
a = \((L/3)\)*1
b = \((L/3)\)*2
Ee = 10000000.0
Ii = 3.5729300
T = 1/2*ma*\((\((qa')\))\)^2 + 1/2*mb*\((\((qb')\))\)^2
+ \ 1/2*ρ*A*\((∑\+\(i = 1\)\%n\(∑\+\(j = 1\)\%n\((
q')\)*\((q[ j]')\)*
\(∫\_0\%L\((\((Sin[\((i*π*x)\)/L])\)*
\((Sin[\((j*π*x)\)/L])\))\) \x\)\))\)
V = 1/2*ka* \((∑\+\(i = 1\)\%n\(∑\+\(j = 1\)\%n\((q)\)*Sin[\((i*π*a)\)/L]*
\(( q)\)*Sin[\((j*π*a)\)/L]\) -
2*qa*\(∑\+\(i = \1\)\%n\((q)\)*
Sin[\((i*π*a)\)/L]\) + \((qa)\)^2)\) +
1/2*kb* \((∑\+\(i = 1\)\%n\(∑\+\(j =
1\)\%n\((q)\)*Sin[\((i*π*b)\)/L]*
\((q[ j])\)*Sin[\((j*π*b)\)/L]\) - 2*qb*\(∑\+\(i =
1\)\%n\((q)\)*Sin[\((i*π*b)\)/L]\) + \((qb)\)^2)\) +
1/2*Ee*Ii*
\(∑\+\(i = 1\)\%n\(∑\+\(j = 1\)\%n\((\((q)\)*\((q)\)*
\(∫\_0\%L D, {
x, 2}]*D, {
x, 2}] \x\))\)\)\)
f = 1.0
QF1 = Exp*\(∫\_0\%L f*
Sin[\((1*π*x)\)/L] \x\)
QF2 = Exp[I*ω*
t]*\(∫\_0\%L f*Sin[\((2*π*x)\)/
L] \x\)
Q = {QF1, QF2, 0, 0}
LagrangianEquations
% /. \((q)\) -> Q1[ω]*Exp
% /. \((q')\) -> I*ω*Q1[ω]*Exp
% /. \((\((
q')\)')\) -> \((\(-ω^2\))\)*Q1[ω]*Exp
% /. \((q)\) -> Q2[ω]*Exp
% /. \((q')\) -> I*ω*Q2[ω]*Exp
% /. \((\((q')\)')\)[
t] -> \((\(-ω^2\))\)*Q2[ω]*Exp
% /. qa -> Qa[ω]*Exp
% /. \((qa')\) -> I*ω*Qa[ω]*Exp
% /. \((\((qa')\)')\) -> \((\(-ω^2\))\)*Qa[ω]*Exp
% /. qb -> Qb[ω]*Exp
% /. \((qb')\) -> I*ω*Qb[ω]*Exp
LE = % /. \((\((
qb')\)')\) -> \((\(-ω^2\))\)*Qb[ω]*Exp
eqn1 = LE[\((1)\)]
eqn2 = LE[\((2)\)]
eqna = LE[\((3)\)]
eqnb = LE[\((4)\)]
δ = 0.05
k = 10000.0
ca = 4.37093503
cb = 1.095805147
ka = k + I*\((ω*ca + k*δ)\)
kb = k + I*\((ω*cb + k*δ)\)
Solve[{eqn1[
t], eqn2, eqna, eqnb}, {Qa[ω], Qb[
ω], Q1[ω], Q2[ω]}]
QQ2[ω_] = Simplify /. %]
frf1[ω_] = QQ2[ω/f]
frf[ω_] = frf1[ω]
Mag[ω_] = Sqrt[\((Re])\)^2 + \((Im])\)^2]
Pha[ω_] = Arg]
t = 0
plot], {ω, 0, 3000}]
plot], {ω, 0, 3000}]
plot], {ω, 0, 3000}]
plot], {ω, 0, 3000}]
plot, {ω, 0, 3000}]
plot, {ω, 0, 3000}]
[ 本帖最后由 suffer 于 2007-4-12 21:10 编辑 ] 没高手吗？ 呵呵，你觉得你贴成这样，会有人看的懂么？ 那应该怎样贴 原帖由 zhxbdlut 于 2007-4-3 10:03 发表
那应该怎样贴
已经帮你修正 怎样做的？ 原帖由 zhxbdlut 于 2007-4-14 15:16 发表
怎样做的？
采用引用或者代码就可以了
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