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pythonnumpymatplotlibplotpcm

How to plot a PCM wave using the binary inputs from a .txt file

In my case I will have a PCM.txt file which contains the binary representation of a PCM data like below.

[1. 1. 0. 1. 0. 1. 1. 1. 1. 1. 0. 1. 1. 1. 1. 1. 1. 1. 0. 1. 1. 1. 0. 1. 0. 1. 0. 1. 0. 0. 1. 0. 0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 1. 0. 0. 1. 0. 1. 0. 1. 0. 1. 0. 1. 1. 1. 1. 1. 0. 1. 1. 1. 1. 1. 1. 1. 0. 1. 1. 1. 0. 1. 0. 1. 0. 1. 0. 0. 1. 0. 0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 1. 0. 0. 1. 0. 1.]

1's meaning binary 1

0's meaning binary 0

This is nothing but 100 samples of data.

  1. Is it possible to implement a python code which will read this PCM.txt as the input and plot this PCM data using matplotlib. ? Could you please give me some tips to implement this scenario ?
  2. Will this plotted figure look like a square wave ?
Solution

  • I think you want this:

    import matplotlib.pyplot as plt 
import numpy as np

x = np.arange(100)
y = [1.,1.,0.,1.,0.,1.,1.,1.,1.,1.,0.,1.,1.,1.,1.,1.,1.,1.,0.,1.,1.,1.,0.,1.,0.,1.,0.,1.,0.,0.,1.,0.,0.,0.,0.,0.,1.,0.,0.,0.,0.,0,0.,0.,1.,0.,0.,1.,0.,1.,0.,1.,0.,1.,0.,1.,1.,1.,1.,1.,0.,1.,1.,1.,1.,1.,1.,1.,0.,1.,1.,1.,0.,1.,0.,1.,0.,1.,0.,0.,1.,0.,0.,0.,0.,0.,1.,0.,0.,0.,0.,0.,0.,0.,1.,0.,0.,1.,0.,1.]

plt.step(x, y)
plt.show()

    enter image description here

    If you are having trouble reading the file, you can just use a regex to find things that look like numbers:

    import matplotlib.pyplot as plt 
import numpy as np
import re

# Slurp entire file
with open('data') as f:
    s = f.read()

# Set y to anything that looks like a number
y = re.findall(r'[0-9.]+', s)

# Set x according to number of samples found
x = np.arange(len(y))

# Plot that thing
plt.step(x, y)
plt.show()