NDSolve, Loop, Table, Plot
- To: mathgroup at smc.vnet.net
- Subject: [mg77583] NDSolve, Loop, Table, Plot
- From: Solver <shawnleroux at hotmail.com>
- Date: Wed, 13 Jun 2007 07:35:30 -0400 (EDT)
Hi, I have a system of 3 differential equations and I would like to numerically solve them for different values of one parameter (e.g., p1 = 0.5, 0.6, 0.7, 0.8, etc). Then, I want to 1) make a table for the results of B0[200], B1[200], and B2[200] for all values of p1 and 2) make plots of B0, B1, B2 through time for the different values of p1. Below is the code I tried. The table seems to work sometimes but when I run the code multiple times, the output is the same for all values of p1 (i.e., {{3.99315, 3.99315, 3.99315, 3.99315, 3.99315, 3.99315}, { 0.0813405, 0.0813405, 0.0813405, 0.0813405, 0.0813405, 0.0813405}, {0.021349, 0.021349, 0.021349, 0.021349, 0.021349, 0.021349}}. I don't understand why? The Plot function gives me multiple plots but they are always the same, so it is not drawing plots for the different values of p1. J = 1; r0 = 0.2; r1 = 0.2; r2 = 0.2; p1 = 0.1; dB0 = J - r0*B0[t] - B0[t]*B1[t]; dB1 = p1*B0[t]*B1[t] - r1*B1[t] - B1[t]*B2[t]; dB2 = p2*B1[t]*B2[t] - r2*B2[t]; A = Flatten[Map[({B0[200], B1[200], B2[200]} /. # ) &, sol = Table[NDSolve[{B0'[t] == dB0, B1'[t] == dB1, B2'[t] == dB2, B0[0] == 1, B1[0] == 1, B2[0] == 1}, {B0, B1, B2}, {t, 0, 200}], {p1, 0.5, 1, 0.1}]], 1] // Transpose Export["A.csv", A]; Do[Plot[Evaluate[{B0[t], B1[t], B2[t]} /. sol, {t, 0, 200}, PlotStyle - > {{RGBColor[1, 0, 0]}, {RGBColor[0, 1, 0]}, {RGBColor[0, 0, 1]}}]], {p1, 0.5, 1, 0.1}] Thanks!