message: Update secondordertimedep operator comment
diff: @@ -606,23 +606,22 @@ public:
  using TimeDependentOperator::ImplicitSolve;
  /** @brief Solve the equation:
  - @a k = f(@a x + 1/2 @a dt0^2 @a k, @a dxdt + @a dt1 @a k, t), for the
  + @a k = f(@a x + @a fac0 @a k, @a dxdt + @a fac1 @a k, t), for the
  unknown @a k at the current time t.
  For general F and G, the equation for @a k becomes:
  - F(@a x + 1/2 @a dt0^2 @a k, @a dxdt + @a dt1 @a k, t)
  - = G(@a x + 1/2 @a dt0^2 @a k, @a dxdt + @a dt1 @a k, t).
  + F(@a x + @a fac0 @a k, @a dxdt + @a fac1 @a k, t)
  + = G(@a x + @a fac0 @a k, @a dxdt + @a fac1 @a k, t).
  - The input vector @a x corresponds to time index (or cycle) n, while the
  + The input vectors @a x and @a dxdt corresponds to time index (or cycle) n, while the
  currently set time, #t, and the result vector @a k correspond to time
  - index n+1. The time step @a dt corresponds to the time interval between
  - cycles n and n+1.
  + index n+1.
  This method allows for the abstract implementation of some time
  integration methods.
  If not re-implemented, this method simply generates an error. */
  - virtual void ImplicitSolve(const double dt0, const double dt1,
  + virtual void ImplicitSolve(const double fac0, const double fac1,
  const Vector &x, const Vector &dxdt, Vector &k);
  