Solve this differential equation numerically $,$ on matlab please explain how $?$

$\%$ Define parameters

m$\_$crank $=1$;$\%kg$

$I_{{?}_c\text{r}\text{a}\text{n}\text{k}}=0\mathrm{.}5$;$\%k{g}^{**}{m}^{{?}^{{?}^{?}}}2$

m$\_$rod $=2$;$\%kg$

m$\_$slider $=3$;$\%kg$

$1\_$crank $=1$;$\%m$

$1_{?}$rod $=2$;$\%m$

$g=9\mathrm{.}81$;$\%\frac{m}{s^{{?}^{{?}^{?}}}}2$

$\%$ Define symbolic variables

theta $=$ sym $(\text{'}$theta$\text{'})$;

$x=sym{(}^{\text{'}}{x}^{\text{'}})$;

omega theta$)$;

$v_{{?}_s\text{l}\text{i}\text{d}\text{e}\text{r}}=$diff$(x)$;

$\%$ Define kinetic and potential energies

T$\_$crank $={0\mathrm{.}5}^{**}$ I$\_$crank ${?}^{**}$ omega ${?}^{{?}^{{?}^{?}}}2$;

T$\_$slider $={0\mathrm{.}5}^{**}\_$slider ${?}^{**}{V}_{-}$slider$^{?}^{{?}^{{?}^{?}}}$;

V$\_$slider $=$ m$\_$slider$*{?}^{**}x$;

$T=T_{-}$crank $+$ T$\_$rod $+$ T$\_$slider;

$V=V_{-}$slider;

$\%$ Define Lagrange equations

$L=T-V$;

$L_{-}$theta $,$ theta