You can use the demand matrix calibration to project a PrT demand matrix with the help of count data (Fundamentals: Calibrating PrT matrices).
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Note: You cannot combine the procedure demand matrix calibration with LUCE equilibrium assignment or Tribut equilibrium assignment. |
1. Make sure that the counted volumes are provided as AddValue data of links (Links: Basis tab).
2. Make sure, that the network contains a PrT assignment result (routes via this link).
3. Make sure, that the existing demand matrix is an optimally generated matrix which may have resulted from previous counts or calculations and whose inner structure must correctly represent the impedance situation in the network.
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Note: Representative cross-sections can be used to compensate for significant changes (for example closing of a company with a large work force or the construction of a new residential area). |
4. Make sure that the network has been calibrated at the best for route choice.
5. On the toolbar, click the 
Open 'Procedure sequence' window button.
The Procedure sequence window opens.
6. To the procedure sequence, at the position of your choice, add the Demand matrix calibration procedure of the Matrices category (Setting up and starting the procedure sequence).
7. In the row of the inserted procedure, click the button in the Reference object(s) column.
The Select demand segment window opens.
8. In the selection list, click the PrT demand segment whose demand matrix you would like to calibrate.
9. Confirm with OK.
The demand segment selected is listed in the Reference object(s) column.
10. Make sure the added procedure is highlighted. Then, in the Operations section, click the Edit button.
The Parameters: Matrix calibration (Lohse) window opens.
11. Make the desired changes.
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Element |
Description |
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Count data from |
Via the selection list you may pick the Link-AddValue that is coding the census data. |
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Max. number of iterations |
After the user-defined number of iterations the iteration process is canceled though convergence has not been reached yet. |
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Threshold of precision |
Criterion for termination of the multi-procedure (Fundamentals: Projection) Note The higher the value, the longer the computing time and the higher the precision of the calculations. |
12. Confirm with OK.
13. Execute the procedure (Executing procedures in the procedure sequence).
The demand matrix of the PrT demand segment selected is calibrated.
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Tip: You can verify the calibration by graphical or tabular display of the computation results.
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