Python繪製動畫示例
阿新 • • 發佈:2018-12-10
照貓畫虎,首先看看Python matpotlib官網http://matplotlib.org/examples/index.html上的示例都完成了什麼功能,畢竟自己研究API太費時
1、
import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation def data_gen(t=0): cnt = 0 while cnt < 1000: cnt += 1 t += 0.1 yield t, np.sin(2*np.pi*t) * np.exp(-t/10.) def init(): ax.set_ylim(-1.1, 1.1) ax.set_xlim(0, 10) del xdata[:] del ydata[:] line.set_data(xdata, ydata) return line, fig, ax = plt.subplots() line, = ax.plot([], [], lw=2) ax.grid() xdata, ydata = [], [] def run(data): # update the data t, y = data xdata.append(t) ydata.append(y) xmin, xmax = ax.get_xlim() if t >= xmax: ax.set_xlim(xmin, 2*xmax) ax.figure.canvas.draw() line.set_data(xdata, ydata) return line, ani = animation.FuncAnimation(fig, run, data_gen, blit=False, interval=10, repeat=False, init_func=init) plt.show()
2、
import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation fig = plt.figure() def f(x, y): return np.sin(x) + np.cos(y) x = np.linspace(0, 2 * np.pi, 120) y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1) im = plt.imshow(f(x, y), animated=True) def updatefig(*args): global x, y x += np.pi / 15. y += np.pi / 20. im.set_array(f(x, y)) return im, ani = animation.FuncAnimation(fig, updatefig, interval=50, blit=True) plt.show()
3、
import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation def update_line(num, data, line): line.set_data(data[..., :num]) return line, fig1 = plt.figure() data = np.random.rand(2, 25) l, = plt.plot([], [], 'r-') plt.xlim(0, 1) plt.ylim(0, 1) plt.xlabel('x') plt.title('test') line_ani = animation.FuncAnimation(fig1, update_line, 25, fargs=(data, l), interval=50, blit=True) # To save the animation, use the command: line_ani.save('lines.mp4') fig2 = plt.figure() x = np.arange(-9, 10) y = np.arange(-9, 10).reshape(-1, 1) base = np.hypot(x, y) ims = [] for add in np.arange(15): ims.append((plt.pcolor(x, y, base + add, norm=plt.Normalize(0, 30)),)) im_ani = animation.ArtistAnimation(fig2, ims, interval=50, repeat_delay=3000, blit=True) # To save this second animation with some metadata, use the following command: # im_ani.save('im.mp4', metadata={'artist':'Guido'}) plt.show()
4、
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.patches as patches
import matplotlib.path as path
import matplotlib.animation as animation
fig, ax = plt.subplots()
# histogram our data with numpy
data = np.random.randn(1000)
n, bins = np.histogram(data, 100)
# get the corners of the rectangles for the histogram
left = np.array(bins[:-1])
right = np.array(bins[1:])
bottom = np.zeros(len(left))
top = bottom + n
nrects = len(left)
# here comes the tricky part -- we have to set up the vertex and path
# codes arrays using moveto, lineto and closepoly
# for each rect: 1 for the MOVETO, 3 for the LINETO, 1 for the
# CLOSEPOLY; the vert for the closepoly is ignored but we still need
# it to keep the codes aligned with the vertices
nverts = nrects*(1 + 3 + 1)
verts = np.zeros((nverts, 2))
codes = np.ones(nverts, int) * path.Path.LINETO
codes[0::5] = path.Path.MOVETO
codes[4::5] = path.Path.CLOSEPOLY
verts[0::5, 0] = left
verts[0::5, 1] = bottom
verts[1::5, 0] = left
verts[1::5, 1] = top
verts[2::5, 0] = right
verts[2::5, 1] = top
verts[3::5, 0] = right
verts[3::5, 1] = bottom
barpath = path.Path(verts, codes)
patch = patches.PathPatch(
barpath, facecolor='green', edgecolor='yellow', alpha=0.5)
ax.add_patch(patch)
ax.set_xlim(left[0], right[-1])
ax.set_ylim(bottom.min(), top.max())
def animate(i):
# simulate new data coming in
data = np.random.randn(1000)
n, bins = np.histogram(data, 100)
top = bottom + n
verts[1::5, 1] = top
verts[2::5, 1] = top
return [patch, ]
ani = animation.FuncAnimation(fig, animate, 100, repeat=False, blit=True)
plt.show()
5、將動畫儲存視訊檔案,先安裝 sudo apt -get install ffmpeg
import numpy as np
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
import matplotlib.animation as animation
def update_line(num, data, line):
line.set_data(data[..., :num])
return line,
# Set up formatting for the movie files
Writer = animation.writers['ffmpeg']
writer = Writer(fps=15, metadata=dict(artist='Me'), bitrate=1800)
fig1 = plt.figure()
data = np.random.rand(2, 25)
l, = plt.plot([], [], 'r-')
plt.xlim(0, 1)
plt.ylim(0, 1)
plt.xlabel('x')
plt.title('test')
line_ani = animation.FuncAnimation(fig1, update_line, 25, fargs=(data, l),
interval=50, blit=True)
FFwriter = animation.FFMpegWriter()
line_ani.save('basic_animation.mp4', writer = FFwriter, fps=30, extra_args=['-vcodec', 'libx264'])
#line_ani.save('lines.mp4', writer=writer)
fig2 = plt.figure()
x = np.arange(-9, 10)
y = np.arange(-9, 10).reshape(-1, 1)
base = np.hypot(x, y)
ims = []
for add in np.arange(15):
ims.append((plt.pcolor(x, y, base + add, norm=plt.Normalize(0, 30)),))
im_ani = animation.ArtistAnimation(fig2, ims, interval=50, repeat_delay=3000,
blit=True)
#im_ani.save('im.mp4', writer=writer)