我正在用 Python 來(lái)回答這個(gè)問(wèn)題，即一群外星人是否應(yīng)該帶來(lái) 500 萬(wàn)人口和 100 萬(wàn)資源負(fù)載 vs 1M 人口和 500 萬(wàn)負(fù)載......我試圖找出哪個(gè)這兩種選擇將使 200 年后新星球上的人口最大化。這是我的代碼：這是我的導(dǎo)數(shù)函數(shù)def derivs3(y1, t):    c = P0 + R0    r = a / c    q = (a + b) / c    Pi = y1[0]    Ri = y1[1]    Wi = y1[2]    # the model equations    dPdt = q * Pi*Ri/(1+Wi)    dRdt = - q * Pi*Ri/(1+Wi) + (a / q) * Wi / (t + .0001)    dWdt = b    return [dPdt, dRdt, dWdt]在這里，我定義了我的參數(shù)：# model parametersa = 0.02   # related to conversion of unallocated resources into populationb = 0.0001   # related to growth of knowledgeW0 = 0.0     # initial amount of knowledge# time periodTmax = 600 # years這是我運(yùn)行 odeint 并繪制結(jié)果的位置：# Put your code heret  = np.arange(0, Tmax, 0.1)P0 = 5R0 = 1y0 = [P0,R0,W0]soln = odeint(derivs3, y0, t)PSol = soln[:, 0]RSol = soln[:, 1]WSol = soln[:, 2]P0 = 1R0 = 5y0 = [P0,R0,W0]soln = odeint(derivs3, y0, t)PSol2 = soln[:, 0]RSol2 = soln[:, 1]WSol2 = soln[:, 2]plt.plot(t,PSol)plt.plot(t,PSol2)plt.legend(("5Bil Aliens, 1Bil Resources","1Bil Aliens, 5Bil Resources"), loc='upper left', prop={'size':15}, bbox_to_anchor=(1,1))plt.grid()plt.xlabel("time (years)")plt.ylabel("Population (billions)")plt.title("Populations vs. Time")這就是問(wèn)題出現(xiàn)的地方：if PSol[200] > PSol2[200]:    print("To maximize population after 200 years (for a total of", round(PSol[200],2),"billion aliens), the aliens should take a population of 5 Billion Aliens, and a load of 1 Billion Resources.")elif PSol[200] < PSol2[200]:    print("To maximize population after 200 years (for a total of", round(PSol2[200],2),"billion aliens), the aliens should take a population of 1 Billion Aliens, and a load of 5 Billion Resources.")else:所以它返回以下打印語(yǔ)句，這些語(yǔ)句與我得到的圖表不一致。這可能是索引的問(wèn)題，但我使用 PSol[200] 和 PSol2[200] 因?yàn)槲蚁胫廊绻麄兿朐?200 年后最大化人口，他們應(yīng)該帶多少外星人和資源。見(jiàn)下文（忽略大約 600 年的線，因?yàn)槲覜](méi)有調(diào)整它們，知道它們會(huì)返回相同的問(wèn)題）：這是圖表。我知道這是對(duì)的（詢問(wèn)幫助室），所以它必須是關(guān)閉的索引值。