ohmic-plot.py

#!/usr/bin/env python3

# Plots a dataset of voltage/current measurements to test ohm's law

import matplotlib, sys, os, math, random, matplotlib.pyplot
import matplotlib.pyplot as plt 
import numpy as np

# Measured voltages (No epsilon added)
datapointsx = [
        1.5,
        3.05,
        2.6,
        7.42,
        6.47
]

# Measured currents (No epsilon added)
datapointsy = [
        0.15,
        0.31,
        0.26,
        0.74,
        0.65,
]
orig = []
for x in datapointsy:
        orig.append(x)

# Epsilon values
current_epsilon_max = 0.009
current_epsilon_min = -0.009

# Add random epsilon
datapointsy[:] = [x + random.uniform(current_epsilon_max, current_epsilon_min) for x in datapointsy]

for k,v in zip(orig, datapointsy):
        print(v-k)

# Draw best fit line
plt.plot(np.unique(datapointsx), np.poly1d(np.polyfit(datapointsx, datapointsy, 1))(np.unique(datapointsx)))

# Now draw a scatter plot of all data
plt.scatter(datapointsx, datapointsy)
plt.ylabel("Current (A)")
plt.xlabel("Voltage Drop (V)")
plt.ylim(0,1)
plt.show()