用Python畫一個(gè)平面的太陽(yáng)系得到一些朋友的欣賞，然后有同學(xué)提出了繪制三維太陽(yáng)系的要求。

從Python畫圖的角度來(lái)說(shuō)，三維太陽(yáng)系其實(shí)并不難，問(wèn)題在于八大行星對(duì)黃道面的傾斜太小，所以盡管畫個(gè)三維的圖，但就觀感而言，無(wú)非是把二維的嵌入到三維空間罷了。

來(lái)點(diǎn)小行星

代碼如下

from os import cpu_countimport numpy as npfrom numpy.random import randimport matplotlib.pyplot as pltfrom matplotlib import animationau,G,RE,ME = 1.48e11,6.67e-11,1.48e11,5.965e24m = np.array([3.32e5,0.055,0.815,1,0.107,317.8])*ME*Gr = np.array([0,0.387,0.723,1,1.524,5.203])*REv = np.array([0,47.89,35.03,29.79,24.13,13.06])*1000theta = rand(len(m))*np.pi*2cTheta,sTheta = np.cos(theta), np.sin(theta)xyz = r*np.array([cTheta, sTheta, 0*r])     #位置三分量，因?yàn)閰?shù)太多，所以把這三個(gè)分量寫在了一起uvw = v*np.array([-sTheta, cTheta, 0*v])    #速度三分量N_ast = 100m_ast = rand(N_ast)*1e20r_ast = (rand(N_ast)*3.5+1.6)*REv_ast = np.sqrt(G*3.32e5*ME/r_ast)  #小行星速度sqrt(GM/R)theta = rand(N_ast)*np.pi*2phi = (rand(N_ast)-0.5)*0.3     #給一個(gè)隨機(jī)的小傾角cTheta,sTheta = np.cos(theta), np.sin(theta)cPhi,sPhi = np.cos(phi),np.sin(phi)xyza = r_ast*np.array([cTheta*cPhi, sTheta*cPhi, sPhi])uvwa = v_ast*np.array([-sTheta*cPhi, cTheta*cPhi, sPhi])name = "solar.gif"fig = plt.figure(figsize=(10,10))ax = fig.add_subplot(projection="3d")ax.grid()ax.set_xlim3d([-5.5*RE,5.5*RE])ax.set_ylim3d([-5.5*RE,5.5*RE])ax.set_zlim3d([-5.5*RE,5.5*RE])traces = [ax.plot([],[],[],"-", lw=0.5)[0] for _ in range(len(m))]pts = [ax.plot([],[],[],marker="o")[0] for _ in range(len(m))]pt_asts = [ax.plot([],[],[],marker=".")[0] for _ in range(N_ast)]N = 500dt = 3600*50ts =  np.arange(0,N*dt,dt)xyzs,xyzas = [],[]for _ in ts:    xyz_ij = (xyz.reshape(3,1,len(m))-xyz.reshape(3,len(m),1))    r_ij = np.sqrt(np.sum(xyz_ij**2,0))    xyza_ij = (xyz.reshape(3,1,len(m))-xyza.reshape(3,N_ast,1))    ra_ij = np.sqrt(np.sum(xyza_ij**2,0))        for j in range(len(m)):        for i in range(len(m)):            if i!=j :                uvw[:,i] += m[j]*xyz_ij[:,i,j]*dt/r_ij[i,j]**3        for i in range(N_ast):            uvwa[:,i] += m[j]*xyza_ij[:,i,j]*dt/ra_ij[i,j]**3        xyz += uvw*dt    xyza += uvwa*dt    xyzs.append(xyz.tolist())    xyzas.append(xyza.tolist())xyzs = np.array(xyzs).transpose(2,1,0)xyzas = np.array(xyzas).transpose(2,1,0)def animate(n):    for i in range(len(m)):        xyz = xyzs[i]        traces[i].set_data(xyz[0,:n],xyz[1,:n])        traces[i].set_3d_properties(xyz[2,:n])        pts[i].set_data(xyz[0,n],xyz[1,n])        pts[i].set_3d_properties(xyz[2,n])    for i in range(N_ast):        pt_asts[i].set_data(xyzas[i,0,n],xyzas[i,1,n])        pt_asts[i].set_3d_properties(xyzas[i,2,n])    return traces+pts+pt_astsani = animation.FuncAnimation(fig, animate,     range(N), interval=10, blit=True)plt.show()ani.save(name)