import matplotlib.pyplot as plt
from numpy import arange
from sk_dsp_comm.sigsys import tri
t = arange(-1,5,.01)
x = tri(t,1.0)
plt.plot(t,x)
plt.show()
#
# To turn on at t = 1, shift t.
#
x = tri(t - 1.0,1.0)
plt.plot(t,x)