Algebraic Variables

Main.AlgebraicVariables History

Show minor edits - Show changes to output

June 16, 2015, at 06:42 PM by 45.56.3.184 -
Deleted lines 0-1:
!! Algebraic Variables
June 16, 2015, at 06:42 PM by 45.56.3.184 -
Changed line 7 from:
(:table border=1 width=50% align=left bgcolor=#EEEEEE cellspacing=0:)
to:
(:table border=1 width=100% align=left bgcolor=#EEEEEE cellspacing=0:)
September 25, 2008, at 06:31 PM by 158.35.225.230 -
Changed lines 3-8 from:
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.
to:
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 06:30 PM by 158.35.225.230 -
Added lines 1-31:
!! 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

(:table border=1 width=50% align=left bgcolor=#EEEEEE cellspacing=0:)
(:cellnr:)
 ! 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
(:tableend:)