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Graphic line plot with matplotlib, text file in pytho
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Graphic line plot with matplotlib, text file in pytho
#1
hello, I want to display a graph using data from a text file with matplotlib and I am having some problems. Data is sent and received via sockets and stored in a text file.

here is my code:
import matplotlib.pyplot as plt



X = []
Y = []




fichier = open('orde.txt', 'r')


for row in fichier:
    row=row.split(' ')
    if len(row)>0:
     X.append(row[0])
     Y.append(row[-1])



plt.xlabel('Time' , fontsize = 12)
plt.ylabel('Amplitude', fontsize = 12)
plt.plot(X, Y ,color = 'red', label = 'signal')

plt.title('Courbe', fontsize = 20)
plt.show()
Larz60+ write Aug-12-2022, 05:24 PM:
Please post all code, output and errors (it it's entirety) between their respective tags. Refer to BBCode help topic on how to post. Use the "Preview Post" button to make sure the code is presented as you expect before hitting the "Post Reply/Thread" button.
Fixed for you this time. Please use bbcode tags on future posts.
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#2
Looks like your data is in a text file, but you are treating it like the file contains floats. You need to read the value strings from the file and convert them to float. You could do this yourself, but I suggest using the csv library or pandas.

csv_reader will remove newlines and split entries by delimiter automatically. It is a cleaner way of doing what you are currently doing, but it does not convert the values to float.
https://docs.python.org/3/library/csv.html

pandas read_csv does all the things csv_reader does and it converts the values from strings to floats.
https://pandas.pydata.org/pandas-docs/st...d_csv.html
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#3
(Aug-12-2022, 06:18 PM)deanhystad Wrote: Looks like your data is in a text file, but you are treating it like the file contains floats. You need to read the value strings from the file and convert them to float. You could do this yourself, but I suggest using the csv library or pandas.

csv_reader will remove newlines and split entries by delimiter automatically. It is a cleaner way of doing what you are currently doing, but it does not convert the values to float.
https://docs.python.org/3/library/csv.html

pandas read_csv does all the things csv_reader does and it converts the values from strings to floats.
https://pandas.pydata.org/pandas-docs/st...d_csv.html



Ah Okay, i will try the link. Thanks
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