The DaysInMonth( year, month ) command computes the number of days in the month month of the year year. It is necessary to specify the year in order to take account of leap years.

$\mathrm{with}\left(\mathrm{Calendar}\right)\:$

$\mathrm{DaysInMonth}\left(2000\,2\right)$

$29$

$\mathrm{DaysInMonth}\left(2001\,2\right)$

$28$

$\mathrm{DaysInMonth}\left(1900\,2\right)$

$28$

$\mathrm{DaysInMonth}\left(1995\,10\right)$

$31$

$\mathrm{DaysInMonth}\left(1582\,10\right)$

$21$

The Calendar[DaysInMonth] command was introduced in Maple 2018.

For more information on Maple 2018 changes, see Updates in Maple 2018.