在 FigureCanvas 上显示的条形图动画中标记轴时遇到问题

Question

我一直在使用中概述的动画方法来创建动画并将它们放置在 tkinter FigureCanvas 上。

我很难以 y 轴刻度标签按我希望的方式显示一系列条形图的动画。我的动画将有 100 帧，每帧由一个使用四个 x 值的条形图组成。数据存储在一个 100×4 的矩阵中，其条目是随机的并且介于 0 和 1 之间。动画的每一帧都出现在 FigureCanvas 上。下面是我到目前为止所做的总结，其中 Player 是上面 link 中定义的 class。

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from tkinter import Tk, TOP, BOTH

root=Tk()
root.geometry('1000x1000')

fig=Figure() 

# Place canvas on figure. Each frame of the animation will place a barplot on the 
#canvas.

canvas = FigureCanvasTkAgg(fig, master=root)
canvas.draw()
canvas.get_tk_widget().pack(side=TOP,fill=BOTH,expand=1)

# Random 100-by-4 matrix, each row of which corresponds to an instant in time. 
M=np.random.rand(100,4)
labels=['a','b','c','d']
num_times=M.shape[0]

def update_bar(i):
    ax=fig.add_subplot(111)
    ax.bar(labels,list(M[i,:]))
    # Want y ticks to be labelled 0, .2, .4, .6, .8 for each frame.
    ax.set_yticks(np.arange(0, 1, step=0.2))


ani = Player(fig, update_bar, maxi=num_times)
root.mainloop()

当我播放动画时，y 轴标签变得一团糟，因为在每一帧中都重新创建了刻度线。（参见显示第八帧的图像。）

有没有办法让我在动画开始之前一次性设置y-tickmark标签？

Answer 1

你应该移动这条线：

ax = fig.add_subplot(111)

out of update_bar 函数：您不需要在每次迭代中使用新的 ax。
然后，在 update_bar 函数中你应该添加这一行：

ax.cla()

为了抹去之前的剧情
最后，我建议添加这一行：

ax.set_ylim(0, 1)

在update_bar函数中，为了保持固定的y轴限制。

完整代码

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from tkinter import Tk, TOP, BOTH
import matplotlib
from matplotlib.animation import FuncAnimation
import mpl_toolkits.axes_grid1

root=Tk()
root.geometry('1000x1000')

fig=Figure()

# Place canvas on figure. Each frame of the animation will place a barplot on the
#canvas.

canvas = FigureCanvasTkAgg(fig, master=root)
canvas.draw()
canvas.get_tk_widget().pack(side=TOP,fill=BOTH,expand=1)

# Random 100-by-4 matrix, each row of which corresponds to an instant in time.
M=np.random.rand(100,4)
labels=['a','b','c','d']
num_times=M.shape[0]

class Player(FuncAnimation):
    def __init__(self, fig, func, frames=None, init_func=None, fargs=None,
                 save_count=None, mini=0, maxi=100, pos=(0.125, 0.92), **kwargs):
        self.i = 0
        self.min=mini
        self.max=maxi
        self.runs = True
        self.forwards = True
        self.fig = fig
        self.func = func
        self.setup(pos)
        FuncAnimation.__init__(self,self.fig, self.func, frames=self.play(),
                                           init_func=init_func, fargs=fargs,
                                           save_count=save_count, **kwargs )

    def play(self):
        while self.runs:
            self.i = self.i+self.forwards-(not self.forwards)
            if self.i > self.min and self.i < self.max:
                yield self.i
            else:
                self.stop()
                yield self.i

    def start(self):
        self.runs=True
        self.event_source.start()

    def stop(self, event=None):
        self.runs = False
        self.event_source.stop()

    def forward(self, event=None):
        self.forwards = True
        self.start()
    def backward(self, event=None):
        self.forwards = False
        self.start()
    def oneforward(self, event=None):
        self.forwards = True
        self.onestep()
    def onebackward(self, event=None):
        self.forwards = False
        self.onestep()

    def onestep(self):
        if self.i > self.min and self.i < self.max:
            self.i = self.i+self.forwards-(not self.forwards)
        elif self.i == self.min and self.forwards:
            self.i+=1
        elif self.i == self.max and not self.forwards:
            self.i-=1
        self.func(self.i)
        self.fig.canvas.draw_idle()

    def setup(self, pos):
        playerax = self.fig.add_axes([pos[0],pos[1], 0.22, 0.04])
        divider = mpl_toolkits.axes_grid1.make_axes_locatable(playerax)
        bax = divider.append_axes("right", size="80%", pad=0.05)
        sax = divider.append_axes("right", size="80%", pad=0.05)
        fax = divider.append_axes("right", size="80%", pad=0.05)
        ofax = divider.append_axes("right", size="100%", pad=0.05)
        self.button_oneback = matplotlib.widgets.Button(playerax, label=u'$\u29CF$')
        self.button_back = matplotlib.widgets.Button(bax, label=u'$\u25C0$')
        self.button_stop = matplotlib.widgets.Button(sax, label=u'$\u25A0$')
        self.button_forward = matplotlib.widgets.Button(fax, label=u'$\u25B6$')
        self.button_oneforward = matplotlib.widgets.Button(ofax, label=u'$\u29D0$')
        self.button_oneback.on_clicked(self.onebackward)
        self.button_back.on_clicked(self.backward)
        self.button_stop.on_clicked(self.stop)
        self.button_forward.on_clicked(self.forward)
        self.button_oneforward.on_clicked(self.oneforward)

def update_bar(i):
    ax.cla()
    ax.bar(labels,list(M[i,:]))
    # Want y ticks to be labelled 0, .2, .4, .6, .8 for each frame.
    ax.set_yticks(np.arange(0, 1, step=0.2))
    ax.set_ylim(0, 1)


ax = fig.add_subplot(111)
ani = Player(fig, update_bar, maxi=num_times)
root.mainloop()

在 FigureCanvas 上显示的条形图动画中标记轴时遇到问题

Having problems labelling axes in a barplot animation shown on a FigureCanvas

python

plot

animation

tkinter

matplotlib

完整代码