import matplotlib.pyplot as plt
import numpy as np
import itertools
import csv

limit = 50
x = np.arange(1, limit)
y1 = []
y2 = []
with open("data1down.csv", "r") as datafile:
    data = csv.reader(datafile, delimiter=",")
    for rows in itertools.islice(data, 1, limit):
        y1.append(float(rows[1]))
with open("data2up.csv", "r") as datafile:
    data = csv.reader(datafile, delimiter=",")
    for rows in itertools.islice(data, 1, limit):
        y2.append(float(rows[1]))
plt.plot(x, y1, color="red")
plt.plot(x, y2, color="blue")
plt.axis([0, 50, 7, 11])
plt.title("Elevator Time: Up vs Down")
plt.xlabel("Time: hundredths of a second")
plt.ylabel("Accel Z axis values")
plt.legend(["down", "up"], loc="upper left")
plt.show()