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Parameters in kinetic law definition


The ParameterVariables property shows the parameter variables that are used in the Expression property of the abstract kinetic law object. Use this property to specify the parameters in the ReactionRate equation. Use the method set to assign ParameterVariables to a kinetic law definition. For more information, see Kinetic Law Definition.


Applies toObjects: abstract kinetic law, kineticlaw
Data typeCell array of character vectors
Data valuesSpecified by kinetic law definition
AccessRead/write in kinetic law definition. Read-only in kinetic law.


Define Michaelis Menten Reaction Kinetics in SimBiology Model

Create a SimBiology model with a reaction.

m1 = sbiomodel("m1");
r1 = addreaction(m1,"A -> B");

Add a kinetic law for the reaction by using the built-in kinetic law (Michaelis Menten). Check the expression of the kinetic law.

kl = addkineticlaw(r1,"Henri-Michaelis-Menten");
ans = 
'Vm*S/(Km + S)'

Query the parameters and species variables defined in the kinetic law.

ans = 2x1 cell

ans = 1x1 cell array

Define Va and Ka as ParameterVariableNames, which correspond to the ParameterVariables Vm and Km defined in the Expression property of the kinetic law. To set these variables, first create the parameter variables as parameter objects (p1, p2) with the names Va and Ka, and then add them to the kinetic law object kl. The species object with the name A is created when the reaction object r1 is created and need not be redefined.

p1 = addparameter(kl,"Va");
p2 = addparameter(kl,"Ka");

Set the variable names for the kinetic law object.

kl.ParameterVariableNames = ["Va","Ka"];
kl.SpeciesVariableNames   = ["A"];

Verified that the reaction rate is expressed correctly in the ReactionRate property of the reaction object

ans =