Plot a live index graph using matplotlib - python

Question

I'm trying to plot a lines graph using matplotlib - python.

The graph should look like below image:

Index lines graph

I used patches.PathPatch to graph the image above, with specific vertices and codes, but I'm facing some technical issues when trying to plot live data above what the desired graph. For each reading, the graph gets regenerated (I get total of 8 figures for 8 unique readings). How do I stop this from happening? I just need the image above to be my background graph (as index graph), and live data to be plotted above that graph.... Also, any way to simplify below code? Any help would be greatly appreciated

import matplotlib.pyplot as plt
from matplotlib.path import Path
import matplotlib.patches as patches
import serial # import Serial Library
import numpy  # Import numpy
from drawnow import *

tempF= []
pressure=[]
arduinoData = serial.Serial('/dev/cu.AdafruitEZ-Link64b9-SPP', 9600) #Creating           our serial object named arduinoData
plt.ion() #Tell matplotlib you want interactive mode to plot live data
cnt=0
fig = plt.figure()
ax = fig.add_subplot(111)

def makeFig(): #Create a function that makes our desired plot
 codes = [Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         Path.MOVETO,
         Path.LINETO,
         Path.LINETO,
         Path.LINETO,
         Path.CLOSEPOLY,
         ]

verts1 = [
    (0, 0), # left, bottom
    (0, 23), # left, top
    (1, 18), # right, top
    (1, 0), # right, bottom
    (0, 0), # ignored
    (1, 0), # left, bottom
    (1, 18), # left, top
    (2, 16), # right, top
    (2, 0), # right, bottom
    (1, 0), # ignored
    (2, 0), # left, bottom
    (2, 16), # left, top
    (3, 15), # right, top
    (3, 0), # right, bottom
    (2, 0), # ignored
    (3, 0), # left, bottom
    (3, 15), # left, top
    (4, 14), # right, top
    (4, 0), # right, bottom
    (3, 0), # ignored
    (4, 0), # left, bottom
    (4, 14), # left, top
    (5, 13), # right, top
    (5, 0), # right, bottom
    (4, 0), # ignored
    (5, 0), # left, bottom
    (5, 13), # left, top
    (6, 12), # right, top
    (6, 0), # right, bottom
    (5, 0), # ignored
    (6, 0), # left, bottom
    (6, 12), # left, top
    (7, 10), # right, top
    (7, 0), # right, bottom
    (6, 0), # ignored
    ]

verts2 = [
    (0, 23), # left, bottom
    (0, 45), # left, top
    (1, 39), # right, top
    (1, 18), # right, bottom
    (0, 23), # ignored
    (1, 18), # left, bottom
    (1, 39), # left, top
    (2, 38), # right, top
    (2, 16), # right, bottom
    (1, 18), # ignored
    (2, 16), # left, bottom
    (2, 38), # left, top
    (3, 34), # right, top
    (3, 15), # right, bottom
    (2, 16), # ignored
    (3, 15), # left, bottom
    (3, 34), # left, top
    (4, 30), # right, top
    (4, 14), # right, bottom
    (3, 15), # ignored
    (4, 14), # left, bottom
    (4, 30), # left, top
    (5, 23), # right, top
    (5, 13), # right, bottom
    (4, 14), # ignored
    (5, 13), # left, bottom
    (5, 23), # left, top
    (6, 19), # right, top
    (6, 12), # right, bottom
    (5, 13), # ignored
    (6, 12), # left, bottom
    (6, 19), # left, top
    (7, 16), # right, top
    (7, 10), # right, bottom
    (6, 12), # ignored
    ]

verts3 = [
    (0, 45), # left, bottom
    (0, 50), # left, top
    (1, 50), # right, top
    (1, 39), # right, bottom
    (0, 45), # ignored
    (1, 39), # left, bottom
    (1, 50), # left, top
    (2, 50), # right, top
    (2, 38), # right, bottom
    (1, 39), # ignored
    (2, 38), # left, bottom
    (2, 50), # left, top
    (3, 50), # right, top
    (3, 34), # right, bottom
    (2, 38), # ignored
    (3, 34), # left, bottom
    (3, 50), # left, top
    (4, 46), # right, top
    (4, 30), # right, bottom
    (3, 34), # ignored
    (4, 30), # left, bottom
    (4, 46), # left, top
    (5, 32), # right, top
    (5, 23), # right, bottom
    (4, 30), # ignored
    (5, 23), # left, bottom
    (5, 32), # left, top
    (6, 28), # right, top
    (6, 19), # right, bottom
    (5, 23), # ignored
    (6, 19), # left, bottom
    (6, 28), # left, top
    (7, 24), # right, top
    (7, 16), # right, bottom
    (6, 19), # ignored
    ]

verts4 = [
    (0, 50), # left, bottom
    (0, 60), # left, top
    (1, 60), # right, top
    (1, 50), # right, bottom
    (0, 50), # ignored
    (1, 50), # left, bottom
    (1, 60), # left, top
    (2, 60), # right, top
    (2, 50), # right, bottom
    (1, 50), # ignored
    (2, 50), # left, bottom
    (2, 60), # left, top
    (3, 60), # right, top
    (3, 50), # right, bottom
    (2, 50), # ignored
    (3, 50), # left, bottom
    (3, 60), # left, top
    (4, 60), # right, top
    (4, 46), # right, bottom
    (3, 50), # ignored
    (4, 46), # left, bottom
    (4, 60), # left, top
    (5, 60), # right, top
    (5, 32), # right, bottom
    (4, 46), # ignored
    (5, 32), # left, bottom
    (5, 60), # left, top
    (6, 60), # right, top
    (6, 28), # right, bottom
    (5, 32), # ignored
    (6, 28), # left, bottom
    (6, 60), # left, top
    (7, 60), # right, top
    (7, 24), # right, bottom
    (6, 19), # ignored
    ]

path = Path(verts1, codes)
path2 = Path(verts2, codes)
path3 = Path(verts3, codes)
path4 = Path(verts4, codes)


patch = patches.PathPatch(path, facecolor='green', alpha=0.8)
patch2 = patches.PathPatch(path2, facecolor='orange', alpha=0.8)
patch3 = patches.PathPatch(path3, facecolor='red', alpha=0.8)
patch4 = patches.PathPatch(path4, facecolor='purple', alpha=0.8)

    #ax.axhline(5, linestyle='--', color='k') # horizontal lines
    #ax.axvline(0, linestyle='--', color='k') # vertical lines

ax.add_patch(patch)
ax.add_patch(patch2)
ax.add_patch(patch3)
ax.add_patch(patch4)

ax.set_xlim(0,7)
ax.set_ylim(0,60)
plt.grid()
plt.show()

plt.plot(tempF, 'ro-', label='sensor 1')       #plot the temperature
plt.legend(loc='upper left')                    #plot the legend
plt.plot(pressure, 'bo-', label='sensor 2')       #plot the temperature
plt.legend(loc='upper left')                    

while True: # While loop that loops forever
    while (arduinoData.inWaiting()==0): #Wait here until there is data
        pass #do nothing
    arduinoString = arduinoData.readline() #read the line of text from the serial port
    dataArray = arduinoString.split(',')   #Split it into an array called     dataArray
    print dataArray[0]
    print dataArray[1]
    temp = float( dataArray[0])            #Convert first element to floating     number and put in temp
    P =    float( dataArray[1])            #Convert second element to floating      number and put in P
    tempF.append(temp)                     #Build our tempF array by appending  temp readings
    pressure.append(P)                     #Building our pressure array by  appending P readings
    drawnow(makeFig)                       #Call drawnow to update our live graph
    plt.pause(.000001)                     #Pause Briefly. Important to keep drawnow from crashing
    cnt=cnt+1
    if(cnt>150):                            #If you have 50 or more points, delete the first one from the array
        tempF.pop(0)                       #This allows us to just see the last 50 data points
        pressure.pop(0)

I'm not sure about your redrawing problem, but have you considered using `fill_between` to make your background image? It may help to simplify the code a little... — tmdavison, Nov 20 '15 at 16:15

score 0 · Answer 1 · answered May 22 '18 at 11:27

Using how your input is currently styled:

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

path1 = pd.DataFrame([(0,0),(0,23),(1,18),(1,0),(0,0),(1,0),(1,18),(2,16),(2,0),(1,0),(2,0),(2,16),(3,15),(3,0),(2,0),(3,0),(3,15),(4,14),(4,0),(3,0),(4,0),(4,14),(5,13),(5,0),(4,0),(5,0),(5,13),(6,12),(6,0),(5,0),(6,0),(6,12),(7,10),(7,0),(6,0),])
path2 = pd.DataFrame([(0,23),(0,45),(1,39),(1,18),(0,23),(1,18),(1,39),(2,38),(2,16),(1,18),(2,16),(2,38),(3,34),(3,15),(2,16),(3,15),(3,34),(4,30),(4,14),(3,15),(4,14),(4,30),(5,23),(5,13),(4,14),(5,13),(5,23),(6,19),(6,12),(5,13),(6,12),(6,19),(7,16),(7,10),(6,12),])
path3 = pd.DataFrame([(0,45),(0,50),(1,50),(1,39),(0,45),(1,39),(1,50),(2,50),(2,38),(1,39),(2,38),(2,50),(3,50),(3,34),(2,38),(3,34),(3,50),(4,46),(4,30),(3,34),(4,30),(4,46),(5,32),(5,23),(4,30),(5,23),(5,32),(6,28),(6,19),(5,23),(6,19),(6,28),(7,24),(7,16),(6,19),])
path4 = pd.DataFrame([(0,50),(0,60),(1,60),(1,50),(0,50),(1,50),(1,60),(2,60),(2,50),(1,50),(2,50),(2,60),(3,60),(3,50),(2,50),(3,50),(3,60),(4,60),(4,46),(3,50),(4,46),(4,60),(5,60),(5,32),(4,46),(5,32),(5,60),(6,60),(6,28),(5,32),(6,28),(6,60),(7,60),(7,24),(6,19),])

p1y = list(path1[1][1::5])
p1y.append(path1[1][32])
p2y = list(path2[1][1::5])
p2y.append(path2[1][32])
p3y = list(path3[1][1::5])
p3y.append(path3[1][32])
p4y = list(path4[1][1::5])
p4y.append(path4[1][32])
xline = np.array(range(len(p1y)))

ax.fill_between(xline, np.zeros(len(p1y)), p1y, facecolor='green', alpha=0.8)
ax.fill_between(xline, p1y, p2y, facecolor='orange', alpha=0.8)
ax.fill_between(xline, p2y, p3y, facecolor='red', alpha=0.8)
ax.fill_between(xline, p3y, p4y, facecolor='purple', alpha=0.8)

ax.set_xlim(0,7)
ax.set_ylim(0,60)

plt.grid()
plt.show()

However, if you can simplify your incoming verts data:

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

path1 = [23, 18, 16, 15, 14, 13, 12, 10]
path2 = [45, 39, 38, 34, 30, 23, 19, 16]
path3 = [50, 50, 50, 50, 46, 32, 28, 24]
path4 = [60, 60, 60, 60, 60, 60, 60, 60]
xline = np.array(range(len(path1)))

ax.fill_between(xline, np.zeros(len(path1)), path1, facecolor='green', alpha=0.8)
ax.fill_between(xline, path1, path2, facecolor='orange', alpha=0.8)
ax.fill_between(xline, path2, path3, facecolor='red', alpha=0.8)
ax.fill_between(xline, path3, path4, facecolor='purple', alpha=0.8)

ax.set_xlim(0,7)
ax.set_ylim(0,60)

plt.grid()
plt.show()

A note of difference, you are using Python 2.6 and this was done using Python 3.6.0 and Matplotlib 2.0.0

I didn't notice until after posting that this was from Nov 2015. — GeorgeLPerkins, May 22 '18 at 11:30

Plot a live index graph using matplotlib - python

1 Answers1