Plot graph with pyplot using input from tkinter spinbox

Question

I am working in a project which needs to plot a graph dynamically as the inputs in a tkinter spinbox is changed.

I have a sample code:

from tkinter import *
from tkinter import font
from tkinter.font import Font
from tkinter import messagebox
print("'Tkinter' module is found as tkinter.")

import matplotlib
matplotlib.use('TkAgg')
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.backend_bases import key_press_handler
from matplotlib.figure import Figure
print("Importing matplotlib from libraries.")


master = Tk()

def ok(x_val=1000,y_val=20):
         fig = Figure(figsize=(5,5),dpi=70)
         ax = fig.subplots()
         ax.set_title("Right Ear")
         ax.set_ylabel("db HL")
         ax.set_xlabel("Frequency")
         ax.set_xlim(100,9000)
         ax.set_ylim(130,-10)
         ax.set_facecolor("#ffd2d2")

         x = [125,250,500,1000,2000,4000,8000]
         ticks = [125,250,500,"1K","2K","4K","8K"]
         xm = [750,1500,3000,6000]

         ax.set_xscale('log', basex=2)
         ax.set_xticks(x)
         ax.set_xticks(xm, minor=True)
         ax.set_xticklabels(ticks)
         ax.set_xticklabels([""]*len(xm), minor=True)


         ax.yaxis.set_ticks([120,110,100,90,80,70,60,50,40,30,20,10,0,-10])


         ax.plot([x_val],[y_val],'r+',markersize=15.0,mew=2)
         ax.grid(color="grey")
         ax.grid(axis="x", which='minor',color="grey", linestyle="--")
         canvas = FigureCanvasTkAgg(fig, master=master)
         canvas.show()
         canvas.get_tk_widget().grid(column=0,row=2,columnspan=3,rowspan=15)

def action():
        print(spin.get())
        canvas.draw()
        ok(spin.get(),10)

spin = Spinbox(master, from_=125,to=8000,command=action)
spin.grid(column=5,row=2)

ok()

This code does not change the plot, I cannot understand how to change it, to be precise, how to use canvas.draw() here to do the work. The spinbox has value range from 125 to 8000, I could not figure out how to take the value of the spinbox every time it changes (can use command= but how to implement) and feed it to the x axis of ax.plot() and plot dynamically. As the value of spinbox changes the plot also changes to the new position and removes the previous plot from the previous position.

ImportanceOfBeingErnest · Accepted Answer · 2018-05-14 20:22:42Z

You need to make the variables you need available. A usual approach is to use a class and make those class variables. Those can then be accessed from within the class (self) or outside as attributes.

from Tkinter import *

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

class PlotClass():
    def __init__(self):
         fig = Figure(figsize=(5,5),dpi=70)
         ax = fig.subplots()
         ax.set_title("Right Ear")
         ax.set_ylabel("db HL")
         ax.set_xlabel("Frequency")
         ax.set_xlim(100,9000)
         ax.set_ylim(130,-10)
         ax.set_facecolor("#ffd2d2")

         x = [125,250,500,1000,2000,4000,8000]
         ticks = [125,250,500,"1K","2K","4K","8K"]
         xm = [750,1500,3000,6000]

         ax.set_xscale('log', basex=2)
         ax.set_xticks(x)
         ax.set_xticks(xm, minor=True)
         ax.set_xticklabels(ticks)
         ax.set_xticklabels([""]*len(xm), minor=True)

         ax.yaxis.set_ticks([120,110,100,90,80,70,60,50,40,30,20,10,0,-10])

         self.line, = ax.plot([],[],'r+',markersize=15.0,mew=2)
         ax.grid(color="grey")
         ax.grid(axis="x", which='minor',color="grey", linestyle="--")
         self.canvas = canvas = FigureCanvasTkAgg(fig, master=master)
         canvas.show()
         canvas.get_tk_widget().grid(column=0,row=2,columnspan=3,rowspan=15)
         self.spin = Spinbox(master, from_=125,to=8000,command=self.action)
         self.spin.grid(column=5,row=2)

    def ok(self, x=1000,y=20):
        self.line.set_data([x],[y])
        self.canvas.draw_idle()

    def action(self):
        self.ok(float(self.spin.get()),10)

master = Tk()
plotter = PlotClass()
plotter.ok(125,10)
master.mainloop()

Note: In newer versions of matplotlib you should use NavigationToolbar2Tk instead of NavigationToolbar2TkAgg.

I asked another question based on @ImportanceOfBeingErnest your answer. [here] (stackoverflow.com/questions/47843511/…)

Collectives™ on Stack Overflow

Plot graph with pyplot using input from tkinter spinbox

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related