matplotlib example correlation (snippet)

Python matplotlib example 'correlation'

Modules used in program:

import sys
import numpy as np
import matplotlib

python correlation

Python matplotlib example: correlation

#!/usr/bin/env python

# Modified code from: 
#  - http://matplotlib.org/examples/user_interfaces/embedding_in_tk.html
#  - https://gist.github.com/chappers/bd910bfb0ed73c509802

import matplotlib
matplotlib.use('TkAgg')
import numpy as np
from scipy.stats import pearsonr, spearmanr, kendalltau
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib.figure import Figure
# check python version to import correct version of tkinter
import sys
if sys.version_info[0] < 3:
    import Tkinter as Tk
else:
    import tkinter as Tk

class App:
    def __init__(self, master):
        # create a container for buttons
        buttonFrame = Tk.Frame(root)
        buttonFrame.pack()

        # create buttons
        self.buttonGenerate = Tk.Button(master=buttonFrame,
                                   text='Generate',
                                   command=self.generateMap)
        self.buttonGenerate.pack(side=Tk.LEFT)
        self.buttonQuit = Tk.Button(master=buttonFrame,
                               text='Quit',
                               command=root.destroy)
        self.buttonQuit.pack(side=Tk.LEFT)

        # create container for text
        textFrame = Tk.Frame(root)
        textFrame.pack()

        # create text
        self.label = Tk.Label(master=textFrame,
                              text="Pearson correlation:\nSpearman rho:\nKendall tau:",
                              justify=Tk.LEFT)
        self.label.pack()

        # create container for plot
        plotFrame = Tk.Frame(root)
        plotFrame.pack(side=Tk.BOTTOM)

        # create plot
        f = Figure(figsize=(5, 4), dpi=100)
        self.ax = f.add_subplot(111)
        self.ax.set_xlim([-0.2, 1.2])
        self.ax.set_ylim([-0.2, 1.2])

        self.canvas = FigureCanvasTkAgg(f, master=plotFrame)
        self.canvas.show()
        self.canvas.get_tk_widget().pack()

    def generateMap(self):
        # generate random line
        c = np.random.rand()
        m = np.random.rand() - c

        # get data points
        pointCnt = 50
        sigma = np.random.rand()
        x = np.random.rand(pointCnt)
        y = m*x + c + sigma * np.random.randn(pointCnt)

        # update text
        corr = pearsonr(x,y)[0]
        rho  = spearmanr(x,y)[0]
        tau  = kendalltau(x,y)[0]
        newVals = """Pearson correlation:\t%.2f\nSpearman rho:\t%.2f\nKendall tau:\t%.2f""" % (corr, rho, tau)
        self.label.config(text=newVals)

        # plot points
        self.ax.clear()
        self.ax.scatter(x, y, marker='s', c='black')
        self.ax.set_xlim([-0.2, 1.2])
        self.canvas.draw()

root = Tk.Tk()
root.title("Correlation Examples")
app = App(root)
root.mainloop()

Python links

Learn Python: https://pythonbasics.org/
Python Tutorial: https://pythonprogramminglanguage.com