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Algebraic Variables

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June 16, 2015, at 12:42 PM by 45.56.3.184 -
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!! Algebraic Variables
June 16, 2015, at 12:42 PM by 45.56.3.184 -
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September 25, 2008, at 12:31 PM by 158.35.225.230 -
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Algebraic states are variables that do not have the differential operator ($) applied in any equation.  These algebraic states are

!!! Consistent Initial Conditions

Forward stepping algorithms such as DASSL, DASPK, or CVODE generally require ordinary differential equations (ODEs) or index-1 differential algebraic equations (DAEs) and consistent initial conditions
.  This is not a restriction with simultaneous methods as used by %blue%A%red%P%black%Monitor.  Also, ODEs or DAEs of any index can be solved.
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Algebraic states are variables that do not have the differential operator ($) applied in any equation.  These algebraic states are declared in the variables section.
September 25, 2008, at 12:30 PM by 158.35.225.230 -
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!! Algebraic Variables

Algebraic states are variables that do not have the differential operator ($) applied in any equation.  These algebraic states are

!!! Consistent Initial Conditions

Forward stepping algorithms such as DASSL, DASPK, or CVODE generally require ordinary differential equations (ODEs) or index-1 differential algebraic equations (DAEs) and consistent initial conditions.  This is not a restriction with simultaneous methods as used by %blue%A%red%P%black%Monitor.  Also, ODEs or DAEs of any index can be solved.


!!! Example

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 ! Example model with 2 algebraic equations
 Model example
  Parameters
    p = 1
  End Parameters
 
  Variables
    v1 = 1
    v2 = 2
  End Variables

  Equations
    v1 = v2 + p
    2*v1 * v2 = v1^2
  End Equations
 End Model
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