URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - Printable Version +- Python Forum (https://python-forum.io) +-- Forum: Python Coding (https://python-forum.io/forum-7.html) +--- Forum: Homework (https://python-forum.io/forum-9.html) +--- Thread: URGENT: How to plot data from text file. Trying to recreate plots from MATLAB (/thread-33586.html) |
URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - JamieAl - May-08-2021 I have the following data saved from a MATLAB code and they have the following form: Quote:0,0.001,0.002,0.003,0.004,0.005,0.006,0.007,0.008,0.009,0.01,0.011,0.012,0.013,0.014,0.015,0.016,0.017,0.018,..and I am trying to recreate my plot from MATLAB that looks like: So I have written the following python code that is not working: XX, YY =[], [] for line in open('RhoMacCormack_sigpt05_cflpt5.txt','r'): values = [float(s) for s in line.split()] XX.append(values[0]) YY.append(values[1]) plt.plot(XX,YY) plt.show()Gives the error: ValueError: could not convert string to float: '0,0.001,0.002,0.003,0.004...Could someone help me get this working? RE: URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - perfringo - May-08-2021 You should provide separator. By default it's whitespace: >>> s = '0,0.001,0.002,0.003,0.004,0.005' >>> s.split() ['0,0.001,0.002,0.003,0.004,0.005'] # no whitespace >>> s.split(',') ['0', '0.001', '0.002', '0.003', '0.004', '0.005'] RE: URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - JamieAl - May-08-2021 (May-08-2021, 08:03 PM)perfringo Wrote: You should provide separator. By default it's whitespace:If I do that I get the plot but it's empty? no data is plotted RE: URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - Marbelous - May-12-2021 If you're not getting points on your plot you must not have data in either XX or YY. Your text of the file makes it seem like it's one line. That might get you XX values but I bet YY is empty. Have you looked??? Try printing values after line 3 and make sure you have valid data to plot. RE: URGENT: How to plot data from text file. Trying to recreate plots from MATLAB - Pedroski55 - Dec-03-2023 Urgent?? There is lots of info on matplotlib around. Here is a simple example to get you started. import numpy import matplotlib.pyplot as plt # for locating minor ticks from matplotlib.ticker import (MultipleLocator, AutoMinorLocator) def myApp(): x = np.arange(0.01, 10.0, 0.01) y = x z = 2*x fig, ax = plt.subplots(num='My Plot') # name of the output window plt.rcParams["figure.figsize"] = [5, 5] # set the size of the output window plt.ion() # to make plot non-blocking, i.e. if multiple plots are launched ax.plot(x, y, color = 'g', label='y = x') ax.plot(x, z, color = 'r', label='y = 2 * x') ax.set_xlim(0, 10) # increasing time ax.set_xlabel('increasing time (s)') ax.set_ylabel('voltage (mV)') ax.set_title('Crazy stuff ...') ax.grid(True) ax.legend() plt.show() |