A sawtooth wave is a signal with amplitude that increases like a ramp in each cycle. Additionally, there are modified versions of the sawtooth wave in which the amplitude decreases like a ramp for part of a cycle.
There is a function in Matlab for synthesizing a sawtooth wave. The basic syntax for using the function is the following:
[y] = sawtooth(2 * pi * f * t,width)
Input Variables:
f – frequency of the signal (scalar in Hz)
t – an array of time samples for a signal.
width – for the width of each cycle when the amplitude is increasing like a ramp. This is a scalar value from [0,1].
Output Variable:
y – an array containing a sawtooth-wave signal.
Further documentation for the function is available here.
One special case of the sawtooth wave is the triangle wave.

