The model contains three varying parameters called S1, S2 and S3 and two constant parameters called k1 and k2. (Note that indeed S1, S2 and S3 are parameters and not species in this model.)

The model contains three rules:

Type Variable Formula
Assignment S3 1 · S2
Rate S1 −k2 · S1
Rate S2 k2 · S1

Note the initial value for parameter S3 is undeclared and must be calculated using the assignmentRule.

The initial conditions are as follows:

Value Units
Value of parameter S1 1 any
Value of parameter S2 1.5 × 10−15 same as S1
Value of parameter S3 undeclared same as S1
Value of parameter k1 0.75 dimensionless
Value of parameter k2 50 second-1