For a set of *.csv files, return *.png graphs of the first and third columns with different colors.

elg_plot_csvs_v2.py

import numpy as np
import matplotlib.pyplot as plt
import csv
import glob
import os

print("Gathering CSVs...")

csvFiles = sorted(glob.glob(os.getcwd() + "/*.csv"))
numpyFileData = []
iteration = 1
voltage = 1
colors = ['red', 'green', 'blue', 'orange', 'purple']

for x in csvFiles:

    print("Found  " + x)

    filename = os.path.splitext(os.path.basename(x))[0]
    saveto = "{}.png".format(filename)

    # .csv files from ELG3155 labs have the following columns:
    # Time (ms) | Raw speed error (mV) | Raw speed (mrad/s) | Reference (mV) |
    # Control output (mV)
    ms, SmV, mrad, RmV, CmV = np.loadtxt(
        x, delimiter=',', skiprows=1, unpack=True)

    plt.title(
        "Trial {}: Aux Feedback at Input Amplitude {} V".format(
            iteration, voltage))
    plt.plot(ms, mrad, color=colors[((iteration - 1) % len(colors))])
    plt.xlabel('Time (ms)')
    plt.ylabel('Raw speed (mrad/s)')

    print("Saving graph to {}".format(saveto))

    plt.savefig(saveto, bbox_inches='tight')
    plt.clf()

    voltage = voltage + 0.5
    iteration = iteration + 1