T 0

T0 - Solution File

There are 7 modes of operation for the APMonitor software. Each produces a solution file upon successful execution. When the solver fails to obtain a feasible solution, no solution file is created.

  1. ss.t0 - Steady-state simulation
  2. mpu.t0 - Model parameter update
  3. rto.t0 - Real-time optimization
  4. sim.t0 - Dynamic simulation
  5. est.t0 - Moving horizon estimation
  6. ctl.t0 - Nonlinear control
  7. sqs.t0 - Sequential simulation

Once the model is initialized with default values from the APM file, the program then looks for default values in the rto.t0 file and ss.t0 file. If these files are used to initialize a dynamic problem, the steady-state values are propogated along the time horizon. As a final step, the program attempts to read the warm-start file for that specific mode. The mode indicates the warm-restart file name (ss.t0, mpu.t0, rto.t0, sim.t0, est.t0, or ctl.t0).


Specifications as calculated or fixed are set by the asterik following a variable name (variable.name *). The specification can be switched to calculated by adding an asterik. The specification can be switched to fixed by removing the asterik. The solution files ss.t0 and rto.t0 are used to specify default values and specifications for dynamic problems. The values and specifications in these files over-write the default values giving in the APM file. Values and specifications in the mode specific t0 file over-write all others.

Order for Specifications and Default Values

  1. APM file
  2. T0 files
    • rto.t0
    • ss.t0
    • mode.t0 (skipped when NLC.COLDSTART=1)

Example File - ss.t0

  Value          Units       Name (*=DOF)
 5.00000000E+00             ss.test.lags.u1  
 2.00000000E+00             ss.test.lags.u2  
 5.00000000E+00             ss.test.lags.x1 *
 2.50000000E+00             ss.test.lags.u3 *