Matplotlib FuncAnimation

[NewPi]

Hi,

I have a question about FuncAnimation of Matplotlib. Here is my code:

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import numpy as np import matplotlib.pyplot as plt import matplotlib as mpl import matplotlib.animation     def update(n):     t = n * delta_t     u = np.cos(k * x - omega * t)     plot.set_ydata(u)     text.set_text(f"t = {t:5.1f}")       return plot, text,     def init():     global plot     global text     plot, = ax.plot(x, np.cos(k * x))     text = ax.text(0.0, 1.05, '')       return plot, text,     if __name__ == '__main__':     x = np.linspace(0, 20, 500)     omega = 1.0     k = 1.0     delta_t = 0.02       fig = plt.figure()     ax = fig.add_subplot(1, 1, 1)     ax.set_ylim(-1.2, 1.2)     ax.set_xlabel("Ort x")     ax.set_ylabel("u(x, t)")     ax.grid()       ani = mpl.animation.FuncAnimation(fig, update, interval=3000, blit=True, init_func=init)     plt.show()

It start's without the line-plot. After 3s there is a line-plot. I don't know, why. I thought, it would start with the init() and after 3s it would call update().

[deanhystad]

Your interval is very long. Try this:

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def init():     global plot     global text     plot, = ax.plot(x, np.cos(k * x))     text = ax.text(0.0, 1.05, '')       return plot, text,     if __name__ == '__main__':     x = np.linspace(0, 20, 500)     omega = 1.0     k = 1.0     delta_t = 0.02       fig = plt.figure()     ax = fig.add_subplot(1, 1, 1)     ax.set_ylim(-1.2, 1.2)     ax.set_xlabel("Ort x")     ax.set_ylabel("u(x, t)")     ax.grid()       ani = mpl.animation.FuncAnimation(fig, update, interval=50, blit=True, init_func=init)     plt.show()

[NewPi]

Hey,

I know, that my interval is very long. I did it on purpose to see how the diagram starts.

I didn't expect, that it start's without the line-plot. I think, I don't understand the FuncAnimation :D :D

[NewPi]

It does what I want, if I say blit=False. But why?