x ( t ) = 2 a ( t − a ⌊ t a + 1 2 ⌋ ) ( − 1 ) ⌊ t a + 1 2 ⌋ {\displaystyle x(t)={\frac {2}{a}}\left(t-a\left\lfloor {\frac {t}{a}}+{\frac {1}{2}}\right\rfloor \right)(-1)^{\left\lfloor {\frac {t}{a}}+{\frac {1}{2}}\right\rfloor }} where the symbol ⌊ n ⌋ {\displaystyle \scriptstyle \lfloor n\rfloor } represent the floor function of n.