在Python上绘制画布上的条形图

Question

我正在尝试使用tkinter将条形图绘制到Canvas小部件上。基于我在互联网上找到的“如何绘制按列分组的条形图”的示例，这是我用来绘制我想要的图形的测试程序：

df=pd.read_excel("testdata.xlsx")

x = 'Gender'
y = 'Sales'

a = df[[x, y]]
a = a.groupby(x).sum()
a.plot(kind='bar',legend=False)
plt.show()

该程序应绘制一个按“性别”分组的条形图，并绘制每个性别的“销售”总和，如this。

所以我试图把这段代码放到我的tkinter代码中，看起来像这样：

f = Figure()
myplot = f.add_subplot(111)
myplot = self.df[[x, y]]               #make a subset df of the columns to   be plotted
myplot = myplot.groupby(x).sum()       #groupby column 'x' and calculate sum
myplot.plot(kind='bar',legend=False)
self.Canvas1 = FigureCanvasTkAgg(f, master=self.top)  #self.top is the main window of the gui
self.Canvas1.get_tk_widget().place(relx=0.045, rely=0.545, relheight=0.4, relwidth=0.91)

我理解这是完全错误的，我将myplot分配给三个不同的东西。我的问题是如何编写正确的代码来创建与上面的代码相同的图？

Answer 1

您为myplot=分配了三个不同的元素，因此我不知道您尝试绘制的内容。

如何在pandas中绘制tkinter数据的简单示例（使用matplotlib）

#!/usr/bin/env python3

#
# http://matplotlib.org/examples/user_interfaces/embedding_in_tk.html
#

# --- matplotlib ---
import matplotlib 
matplotlib.use('TkAgg') # choose backend

from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.pyplot import Figure

# --- other ---
import tkinter as tk
import pandas as pd

# --- for example data --
import random
import math

# --- random data ---

df1 = pd.DataFrame([random.randint(-100, 100) for _ in range(60)])
df2 = pd.DataFrame([math.sin(math.radians(x*6)) for x in range(60)])

# --- GUI ---

root = tk.Tk()

# top frame for canvas and toolbar - which need `pack()` layout manager
top = tk.Frame(root)
top.pack()

# bottom frame for other widgets - which may use other layout manager 
bottom = tk.Frame(root)
bottom.pack()

# --- canvas and toolbar in top ---

# create figure
fig = matplotlib.pyplot.Figure()

# create matplotlib canvas using `fig` and assign to widget `top`
canvas = FigureCanvasTkAgg(fig, top)

# get canvas as tkinter widget and put in widget `top`
canvas.get_tk_widget().pack()

# create toolbar               
toolbar = NavigationToolbar2TkAgg(canvas, top)
toolbar.update()
canvas._tkcanvas.pack()

# --- first plot ---

# create first place for plot
ax1 = fig.add_subplot(211)

# draw on this plot
df1.plot(kind='bar', legend=False, ax=ax1)

# --- second plot ---

# create second place for plot
ax2 = fig.add_subplot(212)

# draw on this plot
df2.plot(kind='bar', legend=False, ax=ax2)

# --- other widgets in bottom ---

b = tk.Button(bottom, text='Exit', command=root.destroy)
b.pack()

# --- start ----

root.mainloop()

Github：furas/python-examples/tkinter/matplot-canvas/example-1

编辑：我创建了示例数据

data = {
    'Gender':['F', 'M', 'F','M'],
    'Sales': [1, 2, 3, 4],
}

df = pd.DataFrame(data)

x = 'Gender'
y = 'Sales'

new_df = df[[x, y]].groupby(x).sum()

然后我用它来显示画布。

# --- matplotlib ---
import matplotlib 
matplotlib.use('TkAgg') # choose backend

from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.pyplot import Figure

# --- other ---
import tkinter as tk
import pandas as pd

# --- GUI ---

root = tk.Tk()

# top frame for canvas and toolbar - which need `pack()` layout manager
top = tk.Frame(root)
top.pack()

# bottom frame for other widgets - which may use other layout manager 
bottom = tk.Frame(root)
bottom.pack()

# --- canvas and toolbar in top ---

# create figure
fig = matplotlib.pyplot.Figure()

# create matplotlib canvas using `fig` and assign to widget `top`
canvas = FigureCanvasTkAgg(fig, top)

# get canvas as tkinter widget and put in widget `top`
canvas.get_tk_widget().pack()

# create toolbar               
toolbar = NavigationToolbar2TkAgg(canvas, top)
toolbar.update()
canvas._tkcanvas.pack()

# --- plot ---

data = {
    'Gender':['F', 'M', 'F','M'],
    'Sales': [1, 2, 3, 4],
}

df = pd.DataFrame(data)

x = 'Gender'
y = 'Sales'

new_df = df[[x, y]].groupby(x).sum()

# create first place for plot
ax = fig.add_subplot(111)

# draw on this plot
new_df.plot(kind='bar', legend=False, ax=ax)


# --- other widgets in bottom ---

b = tk.Button(bottom, text='Exit', command=root.destroy)
b.pack()

# --- start ----

root.mainloop()