controlled stepper following this Controlled Stepper concept provides the
        possibility to perform one step of the solution <span class="emphasis"><em>x(t)</em></span>
        of an ODE with step-size <span class="emphasis"><em>dt</em></span> to obtain <span class="emphasis"><em>x(t+dt)</em></span>
        with a given step-size <span class="emphasis"><em>dt</em></span>. Depending on an error estimate
        of the solution the step might be rejected and a smaller step-size is suggested.
      </p>
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