使用 Matplotlib 可以创建漂亮的图表
from mpl_toolkits.mplot3d import Axes3D
from matplotlib import cm
from matplotlib.ticker import LinearLocator, FormatStrFormatter
import matplotlib.pyplot as plt
import numpy as np
fig = plt.figure() # create a figure
ax = fig.gca(projection='3d') # create a 3-dimensional axis
X = np.arange(-5, 5, 0.25) # horizontal range
Y = np.arange(-5, 5, 0.25) # vertical range
X, Y = np.meshgrid(X, Y) # create a special grid
R = np.sqrt(X**2 + Y**2) # calculate square root
Z = np.sin(R) # calculate sinus
## use #@UndefinedVariable below to ignore the error for cm.coolwarm
surf = ax.plot_surface(X, Y, Z, rstride=1, cstride=1,
cmap=cm.coolwarm, linewidth=0,
antialiased=False)
ax.set_zlim(-1.01, 1.01) # z-axis is third dimension
ax.zaxis.set_major_locator(LinearLocator(10))
ax.zaxis.set_major_formatter(FormatStrFormatter('%.02f'))
fig.colorbar(surf, shrink=0.5, aspect=5)
plt.show() # display the figure
绘制图表
import numpy as np
import matplotlib.pyplot as plt
x = np.arange(0, 5, 0.1)
y = np.sin(x)
plt.plot(x, y)
plt.show()
from pylab import show, arange, sin, plot, pi
t = arange(0.0, 2.0, 0.01)
s = sin(2 * pi * t)
plot(t, s)
show()
在图表上放标签
之前，我们使用的是默认的 Matplotlib GUI，现在，我们使用 tkinter GUI。
虽然 plot 是创建 Matplotlib 图表最简单的方便的方法，但是使用 Figure 结合 Canvas 能够更加定制化。
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import tkinter as tk
#--------------------------------------------------------------
fig = Figure(figsize=(12, 8), facecolor='white')
#--------------------------------------------------------------
# axis = fig.add_subplot(111) # 1 row, 1 column, only graph
axis = fig.add_subplot(211) # 2 rows, 1 column, Top graph
#--------------------------------------------------------------
xValues = [1,2,3,4]
yValues = [5,7,6,8]
axis.plot(xValues, yValues)
axis.set_xlabel('Horizontal Label')
axis.set_ylabel('Vertical Label')
# axis.grid() # default line style
axis.grid(linestyle='-') # solid grid lines
#--------------------------------------------------------------
def _destroyWindow():
root.quit()
root.destroy()
#--------------------------------------------------------------
root = tk.Tk()
root.withdraw()
root.protocol('WM_DELETE_WINDOW', _destroyWindow)
#--------------------------------------------------------------
canvas = FigureCanvasTkAgg(fig, master=root)
canvas._tkcanvas.pack(side=tk.TOP, fill=tk.BOTH, expand=1)
#--------------------------------------------------------------
root.update()
root.deiconify()
root.mainloop()
这里我们首先创建了一个 Figure 对象的实例，接下来我们给该图添加了一个子图 add_subplot(211)。
下面是一个完整的示例：
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import tkinter as tk
#--------------------------------------------------------------
fig = Figure(figsize=(12, 8), facecolor='white')
xValues = [1,2,3,4]
yValues = [5,7,6,8]
#--------------------------------------------------------------
axis1 = fig.add_subplot(221)
axis2 = fig.add_subplot(222, sharex=axis1, sharey=axis1)
axis3 = fig.add_subplot(223, sharex=axis1, sharey=axis1)
axis4 = fig.add_subplot(224, sharex=axis1, sharey=axis1)
#--------------------------------------------------------------
axis1.plot(xValues, yValues)
axis1.set_xlabel('Horizontal Label 1')
axis1.set_ylabel('Vertical Label 1')
axis1.grid(linestyle='-') # solid grid lines
#--------------------------------------------------------------
axis2.plot(xValues, yValues)
axis2.set_xlabel('Horizontal Label 2')
axis2.set_ylabel('Vertical Label 2')
axis2.grid(linestyle='-') # solid grid lines
#--------------------------------------------------------------
axis3.plot(xValues, yValues)
axis3.set_xlabel('Horizontal Label3')
axis3.set_ylabel('Vertical Label 3')
axis3.grid(linestyle='-') # solid grid lines
#--------------------------------------------------------------
axis4.plot(xValues, yValues)
axis4.set_xlabel('Horizontal Label 4')
axis4.set_ylabel('Vertical Label 4')
axis4.grid(linestyle='-') # solid grid lines
#--------------------------------------------------------------
def _destroyWindow():
root.quit()
root.destroy()
#--------------------------------------------------------------
root = tk.Tk()
root.withdraw()
root.protocol('WM_DELETE_WINDOW', _destroyWindow)
#--------------------------------------------------------------
canvas = FigureCanvasTkAgg(fig, master=root)
canvas._tkcanvas.pack(side=tk.TOP, fill=tk.BOTH, expand=1)
#--------------------------------------------------------------
root.update()
root.deiconify()
root.mainloop()
图例
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import tkinter as tk
#--------------------------------------------------------------
fig = Figure(figsize=(12, 5), facecolor='white')
#--------------------------------------------------------------
axis = fig.add_subplot(111) # 1 row, 1 column
xValues = [1,2,3,4]
yValues0 = [6,7.5,8,7.5]
yValues1 = [5.5,6.5,8,6]
yValues2 = [6.5,7,8,7]
t0, = axis.plot(xValues, yValues0)
t1, = axis.plot(xValues, yValues1)
t2, = axis.plot(xValues, yValues2)
axis.set_ylabel('Vertical Label')
axis.set_xlabel('Horizontal Label')
axis.grid()
fig.legend((t0, t1, t2), ('First line', 'Second line', 'Third'
' line'), 'upper right')
#--------------------------------------------------------------
def _destroyWindow():
root.quit()
root.destroy()
#--------------------------------------------------------------
root = tk.Tk()
root.withdraw()
root.protocol('WM_DELETE_WINDOW', _destroyWindow)
#--------------------------------------------------------------
canvas = FigureCanvasTkAgg(fig, master=root)
canvas._tkcanvas.pack(side=tk.TOP, fill=tk.BOTH, expand=1)
#--------------------------------------------------------------
root.update()
root.deiconify()
root.mainloop()
动态调整图表大小
通过set_ylim 和 set_xlim 来限制x，y轴的范围
axis.set_ylim(0, 8) # lower limit (0)
axis.set_xlim(0, 8) # use same limits for x我们真正想做的是根据数据范围动态调整图表，同时限制太高或太低的值。
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import tkinter as tk
#--------------------------------------------------------------
fig = Figure(figsize=(12, 5), facecolor='white')
#--------------------------------------------------------------
axis = fig.add_subplot(111) # 1 row, 1 column
xValues = [1,2,3,4]
yValues0 = [6,7.5,8,7.5]
yValues1 = [5.5,6.5,50,6] # one very high value (50)
yValues2 = [6.5,7,8,7]
yAll = [yValues0, yValues1, yValues2] # list of lists
# flatten list of lists retrieving minimum value
minY = min([y for yValues in yAll for y in yValues])
yUpperLimit = 20
# flatten list of lists retrieving max value within defined limit
maxY = max([y for yValues in yAll for y in yValues if y <
yUpperLimit])
# dynamic limits
axis.set_ylim(minY, maxY)
axis.set_xlim(min(xValues), max(xValues))
t0, = axis.plot(xValues, yValues0)
t1, = axis.plot(xValues, yValues1)
t2, = axis.plot(xValues, yValues2)
axis.set_ylabel('Vertical Label')
axis.set_xlabel('Horizontal Label')
axis.grid()
fig.legend((t0, t1, t2), ('First line', 'Second line', 'Third'
' line'), 'upper right')
#--------------------------------------------------------------
def _destroyWindow():
root.quit()
root.destroy()
#--------------------------------------------------------------
root = tk.Tk()
root.withdraw()
root.protocol('WM_DELETE_WINDOW', _destroyWindow)
#--------------------------------------------------------------
canvas = FigureCanvasTkAgg(fig, master=root)
canvas._tkcanvas.pack(side=tk.TOP, fill=tk.BOTH, expand=1)
#--------------------------------------------------------------
root.update()
root.deiconify()
root.mainloop()
参考文献
- Python GUI Programming Cookbook - Second Edition by Burkhard A. Meier