Is $\displaystyle {r}{\left({t}\right)}$ represented in the table below a function?

t r(t) -4 0 -3 -7 -2 3 -1 7 0 10 1 -1 1 4

$\displaystyle {r}{\left({t}\right)}$ is a function $\displaystyle {r}{\left({t}\right)}$ is not a function