import numpy as np
import matplotlib.pyplot as plt
# this program is much more 'procedural' than good python can be, but we will learn as we go along
n = 100   # the number of points we want to plot

# the following 'loop' is a VERY poor way of making an array or list, but it is easy to understand at this point in the class
x = []   # create an empty list
y = []
for z in np.linspace(0,7,n):    # ‘for loops’ cycle over a list, in this case a list of numbers generated by the numpy ‘linspace’ method, don’t forget the ‘:’
    y.append(np.sin(z))
    x.append(z)                   #create lists of x and y.  Lists must be 'appended' to to extend

fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot(x,y,'r-*')
# could stop here, but can pretty it up a little
xspan = max(x) -min(x)
yspan = max(y) -min(y)
minx = min(x) - 0.05*xspan
maxx = max(x) + 0.05*xspan
miny = min(y) - 0.05*yspan
maxy = max(y) + 0.05*yspan
ax.axis([minx,maxx,miny,maxy])
ax.set_title("Simple Sine plot")
ax.set_xlabel("Radians")

plt.show()