Maxima Function
elapsed_run_time ()
Returns an estimate of the number of seconds (including fractions of a second) which Maxima has spent in computations since Maxima was most recently started or restarted. The return value is a floating-point number.
Example:
(%i1) elapsed_run_time (); (%o1) 0.04 (%i2) expand ((a + b)^500)$ (%i3) elapsed_run_time (); (%o3) 1.26