# file: lecture_07/plot.py
#                                                                              
# revision history:                                                            
#
# 20230911 (JP): initial version
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# This program plots data from a file.
#
# To run this script, do this:
#
#  python plot.py filename.txt
#
#------------------------------------------------------------------------------

# import required system modules                                               
#
import os
import sys
import numpy as np
import matplotlib.pyplot as plt

#------------------------------------------------------------------------------
#
# main program
#
#------------------------------------------------------------------------------
 
# load the data
#
data = np.loadtxt(sys.argv[1], dtype='f', delimiter=',')

# convert to x-y vectors using a matrix transpose
#
#dataT = data.transpose()
#x = dataT[0]
#y = dataT[1]
  
# alternately, slice the matrix
#
x = data[:,0]
y = data[:,1]

# plot the axes
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plt.axis([-5, 5, -5, 5])
  
# plot the data
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plt.plot(x, y)
  
# add the title
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plt.title("Our Data")
  
# addi the labels
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plt.ylabel("y-axis")
plt.xlabel("x-axis")
plt.show()

#
# end of file