LowThrustGVE_EventFcn:

% Stopping event function for low thrust GVE sim using ode solver.
 Terminate when the abs value of difference between current element and
 desired element is less than tolerance.
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   Form:
   [value,isterminal,direction] = LowThrustGVE_EventFcn(t,y,k,ykdes,tol)
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   Inputs
   ------
   t             (1,1)       Time
   y             (6,1)       State vector
   k             (1,1)       Index of element to check (1 <= k <= 6)
   ykdes         (1,1)       Desired value of kth element
   tol           (1,1)       Threshold passing tolerance

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   Outputs
   -------
   value         (1,1)       Value of function evaluation
   isterminal    (1,1)       1 - terminal condition
   direction     (1,1)       0 - direction does not matter

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