python – 如何在matplotlib中为colorbar设置动画
作者:互联网
我有一个动画,其中数据的范围变化很大.我想有一个跟踪数据的最大值和最小值的颜色条(即我希望它不被修复).问题是如何做到这一点.
理想情况下,我希望颜色条在自己的轴上.
我尝试了以下四件事
1.天真的方法
问题:新的颜色条是每帧的绘图
#!/usr/bin/env python
"""
An animated image
"""
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
fig = plt.figure()
ax = fig.add_subplot(111)
def f(x, y):
return np.exp(x) + np.sin(y)
x = np.linspace(0, 1, 120)
y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1)
frames = []
for i in range(10):
x += 1
curVals = f(x, y)
vmax = np.max(curVals)
vmin = np.min(curVals)
levels = np.linspace(vmin, vmax, 200, endpoint = True)
frame = ax.contourf(curVals, vmax=vmax, vmin=vmin, levels=levels)
cbar = fig.colorbar(frame)
frames.append(frame.collections)
ani = animation.ArtistAnimation(fig, frames, blit=False)
plt.show()
2.添加到图像
将上面的for循环更改为
initFrame = ax.contourf(f(x,y))
cbar = fig.colorbar(initFrame)
for i in range(10):
x += 1
curVals = f(x, y)
vmax = np.max(curVals)
vmin = np.min(curVals)
levels = np.linspace(vmin, vmax, 200, endpoint = True)
frame = ax.contourf(curVals, vmax=vmax, vmin=vmin, levels=levels)
cbar.set_clim(vmin = vmin, vmax = vmax)
cbar.draw_all()
frames.append(frame.collections + [cbar])
问题:这引起了提升
AttributeError: 'Colorbar' object has no attribute 'set_visible'
3.在自己的轴上绘图
问题:颜色栏未更新.
#!/usr/bin/env python
"""
An animated image
"""
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
fig = plt.figure()
ax1 = fig.add_subplot(121)
ax2 = fig.add_subplot(122)
def f(x, y):
return np.exp(x) + np.sin(y)
x = np.linspace(0, 1, 120)
y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1)
frames = []
for i in range(10):
x += 1
curVals = f(x, y)
vmax = np.max(curVals)
vmin = np.min(curVals)
levels = np.linspace(vmin, vmax, 200, endpoint = True)
frame = ax1.contourf(curVals, vmax=vmax, vmin=vmin, levels=levels)
cbar = fig.colorbar(frame, cax=ax2) # Colorbar does not update
frames.append(frame.collections)
ani = animation.ArtistAnimation(fig, frames, blit=False)
plt.show()
2和4的组合.
问题:颜色条是不变的.
一个类似的问题是here发布,但看起来OP对固定的颜色条感到满意.
解决方法:
虽然我不确定如何使用ArtistAnimation专门执行此操作,但使用FuncAnimation非常简单.如果我对您的“天真”版本1进行以下修改,则可以正常工作.
修改版本1
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
from mpl_toolkits.axes_grid1 import make_axes_locatable
fig = plt.figure()
ax = fig.add_subplot(111)
# I like to position my colorbars this way, but you don't have to
div = make_axes_locatable(ax)
cax = div.append_axes('right', '5%', '5%')
def f(x, y):
return np.exp(x) + np.sin(y)
x = np.linspace(0, 1, 120)
y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1)
frames = []
for i in range(10):
x += 1
curVals = f(x, y)
frames.append(curVals)
cv0 = frames[0]
cf = ax.contourf(cv0, 200)
cb = fig.colorbar(cf, cax=cax)
tx = ax.set_title('Frame 0')
def animate(i):
arr = frames[i]
vmax = np.max(arr)
vmin = np.min(arr)
levels = np.linspace(vmin, vmax, 200, endpoint = True)
cf = ax.contourf(arr, vmax=vmax, vmin=vmin, levels=levels)
cax.cla()
fig.colorbar(cf, cax=cax)
tx.set_text('Frame {0}'.format(i))
ani = animation.FuncAnimation(fig, animate, frames=10)
plt.show()
主要区别在于我在函数中进行级别计算和轮廓修改,而不是创建艺术家列表.颜色栏有效,因为您可以清除前一帧中的轴并每帧重做一次.
使用轮廓或轮廓f时,必须执行此重做,因为您不能仅动态更改数据.但是,由于您绘制了如此多的轮廓级别并且结果看起来很流畅,我认为您可能最好使用imshow – 这意味着您实际上可以只使用相同的艺术家并更改数据,并且颜色栏会自动更新.它也快得多!
更好的版本
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
from mpl_toolkits.axes_grid1 import make_axes_locatable
fig = plt.figure()
ax = fig.add_subplot(111)
# I like to position my colorbars this way, but you don't have to
div = make_axes_locatable(ax)
cax = div.append_axes('right', '5%', '5%')
def f(x, y):
return np.exp(x) + np.sin(y)
x = np.linspace(0, 1, 120)
y = np.linspace(0, 2 * np.pi, 100).reshape(-1, 1)
# This is now a list of arrays rather than a list of artists
frames = []
for i in range(10):
x += 1
curVals = f(x, y)
frames.append(curVals)
cv0 = frames[0]
im = ax.imshow(cv0, origin='lower') # Here make an AxesImage rather than contour
cb = fig.colorbar(im, cax=cax)
tx = ax.set_title('Frame 0')
def animate(i):
arr = frames[i]
vmax = np.max(arr)
vmin = np.min(arr)
im.set_data(arr)
im.set_clim(vmin, vmax)
tx.set_text('Frame {0}'.format(i))
# In this version you don't have to do anything to the colorbar,
# it updates itself when the mappable it watches (im) changes
ani = animation.FuncAnimation(fig, animate, frames=10)
plt.show()
标签:colorbar,python,matplotlib,animation 来源: https://codeday.me/bug/20190928/1828567.html