Sawtooth or triangle wave

generates a sawtooth wave with period 2`x`

= sawtooth(`t`

)*π* for the elements of the
time array `t`

. `sawtooth`

is similar to the
sine function but creates a sawtooth wave with peaks of –1 and 1. The sawtooth wave
is defined to be –1 at multiples of 2*π* and to increase linearly
with time with a slope of 1/*π* at all other times.