使用Matplotlib繪製3D動圖
主角是FuncAnimation函數,通過不斷地調用func函數來實現動畫,還可以使用save(filename, writer=None, fps=None, dpi=None, codec=None, bitrate=None, extra_args=None, metadata=None, extra_anim=None, savefig_kwargs=None)
來保存動畫,下面我們主要講下FuncAnimation函數的使用
matplotlib.animation.FuncAnimation(fig, func, frames=None, init_func=None, fargs=None, save_count=None, **kwargs)
主要參數
fig: matplotlib.figure.Figure
用來畫圖、變化尺寸或者其他需要的事件的figure對象
func: callable
每一幀調用的函數。
def func(frame, *fargs) -> iterable_of_artists:
第一個參數是下一幀的值,任何額外的參數都可以通過fargs參數得到
frames: iterable, int, generator function, or None, optional
用來傳遞函數和動畫的每一幀的數據源,控制幀的迭代
init_func : callable, optional
用來畫初始幀的函數,這個函數只會在第一幀之前被調用一次。如果沒有給出的話,那麼幀序列中的第一幀將會用來替代。
If blit == True, init_func必須返回可迭代形式fargs: tuple or None, optional
傳遞給每一次func調用的額外的參數
save_count: int,optional
從幀到緩存的值的數量
interval : number, optional
幀間距(單位ms),默認200毫秒
repeat_delay : number, optional
動畫循環間距,默認None
repeat : bool, optional
動畫是否要循環播放,默認爲True
blit : bool, optional
控制是否使用blitting來優化繪圖
官方示例
"""
============
3D animation
============
A simple example of an animated plot... In 3D!
"""
import numpy as np
import matplotlib.pyplot as plt
import mpl_toolkits.mplot3d.axes3d as p3
import matplotlib.animation as animation
def Gen_RandLine(length, dims=2):
"""
Create a line using a random walk algorithm
length is the number of points for the line.
dims is the number of dimensions the line has.
"""
lineData = np.empty((dims, length))
lineData[:, 0] = np.random.rand(dims) # 初始化起點
for index in range(1, length):
# scaling the random numbers by 0.1 so
# movement is small compared to position.
# subtraction by 0.5 is to change the range to [-0.5, 0.5]
# to allow a line to move backwards.
step = ((np.random.rand(dims) - 0.5) * 0.1) # 步長
# 下一步的位置
lineData[:, index] = lineData[:, index - 1] + step
return lineData # 返回一個shape爲(3,25)的數組,3維座標25幀
def update_lines(num, dataLines, lines):
for line, data in zip(lines, dataLines):
# NOTE: there is no .set_data() for 3 dim data...
line.set_data(data[0:2, :num])
line.set_3d_properties(data[2, :num])
return lines
# Attaching 3D axis to the figure
fig = plt.figure()
ax = p3.Axes3D(fig)
# Fifty lines of random 3-D lines (長爲50的數組,每個元素爲shape爲3,25的ndarray,最後實際效果就是50條路徑)
data = [Gen_RandLine(25, 3) for index in range(50)]
# Creating fifty line objects.
# NOTE: Can't pass empty arrays into 3d version of plot()
lines = [ax.plot(dat[0, 0:1], dat[1, 0:1], dat[2, 0:1])[0] for dat in data] # 每條路徑的起始點
# Setting the axes properties
ax.set_xlim3d([0.0, 1.0])
ax.set_xlabel('X')
ax.set_ylim3d([0.0, 1.0])
ax.set_ylabel('Y')
ax.set_zlim3d([0.0, 1.0])
ax.set_zlabel('Z')
ax.set_title('3D Test')
# Creating the Animation object
line_ani = animation.FuncAnimation(fig, update_lines, 25, fargs=(data, lines),
interval=50, blit=False)
plt.show()