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 Author Comment/Response William Duhe 07/11/12 10:37pm Here is my lines of code which produces a very interesting plot: Subscript[M, p] = 100; Subscript[A, r] = -Subscript[C, d]; Subscript[B, m] = 0; Subscript[C, d] = -10^-8*Subscript[M, p]^4; K = 0; Subscript[p, r] = -Subscript[C, d]*a[t]^-4; Subscript[p, m] = Subscript[B, m]*a[t]^-3; Subscript[p, d] = Subscript[C, d]; Subscript[P, r] = Subscript[p, r]/3; Subscript[P, m] = 0; Subscript[P, d] = -Subscript[p, d]; p = Subscript[p, r] + Subscript[p, m] + Subscript[p, d]; P = Subscript[P, r] + Subscript[P, m] + Subscript[P, d]; v = 1/(Sqrt[3]*100); mu = 10^-4*Subscript[M, p]; Y = -mu^3; q = NDSolve[{a''[ t] == -a[t]*1/(6*100^2)*(p + 3 P) + (p/100^4*(3 P + 2 p)), a[0] == 1, a'[0] == 0}, a, {t, -500, 500}] s = NDSolve[{a''[ t] == -a[t]*1/( 6*Subscript[M, p]^2)*(p + 3 P) + (p/Subscript[M, p]^4*(3 P + 2 p)), phi''[t] + 3 (a'[t]/a[t])*phi'[t] - mu^3 == 0, a[0] == 1, phi[0] == 0, a'[0] == 0, phi'[0] == 0}, {a, phi}, {t, -5000, 5000}]; Plot[Evaluate[{phi[t]} /. s], {t, -5000, 5000}, PlotStyle -> Automatic] What would be the best and most efficient way of curve fitting the plot produced? Thanks a lot! URL: ,

 Subject (listing for 'Curve Fitting Complex Diff Eq.') Author Date Posted Curve Fitting Complex Diff Eq. William Duhe 07/11/12 10:37pm Re: Curve Fitting Complex Diff Eq. Bill Simpson 07/12/12 5:27pm
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