def dt_dt(sdat, tstart=None, tend=None):
tseries = sdat.tseries_between(tstart, tend)<EOL>time = tseries['<STR_LIT:t>'].values<EOL>temp = tseries['<STR_LIT>'].values<EOL>dtdt = (temp[<NUM_LIT:1>:] - temp[:-<NUM_LIT:1>]) / (time[<NUM_LIT:1>:] - time[:-<NUM_LIT:1>])<EOL>return dtdt, time[:-<NUM_LIT:1>]<EOL>
Derivative of temperature.

    Compute dT/dt as a function of time using an explicit Euler scheme.

    Args:
        sdat (:class:`~stagpy.stagyydata.StagyyData`): a StagyyData instance.
        tstart (float): time at which the computation should start. Use the
            beginning of the time series data if set to None.
        tend (float): time at which the computation should end. Use the
            end of the time series data if set to None.
    Returns:
        tuple of :class:`numpy.array`: derivative of temperature and time
        arrays.