To Modify a Curve Using Fit
1. Click > 
Modify in Scan Tools.
Modify in Scan Tools.2. Select a curve to modify. The Modify Curve dialog box opens.
3. Click 
.
.4. Type an accuracy value in the Accuracy field.
5. To fit the curve using default settings, click Fit.
6. Optionally, you can set up reference points. To add reference points, click Add Ref Points under Reference Points Setup and select one of the following from the list:
◦ Raw Data Points—Selects raw data points as a reference.
◦ Single Point—Selects a single point as a reference.
◦ Datum Points Array—Selects a datum point array as a reference.
 | When redefining reference points, click Show to show the current reference points. |
7. Click the selection arrow and select reference points.
8. To remove reference points, click Rmv Ref Points and select from All, Raw Data Points, Single Point, and Datum Point Array.
9. Click the selection arrow and select reference points.
| | When redefining reference points, click Show to show the current reference points. |
10. After you have set up the reference points, you can fit the surface again by clicking Fit.
11. Optionally, click Diagnostics to enable the dynamic display of the selected analyses.
12. Optionally, click Constraints to set boundaries constraints.
13. Click OK to finish the operation.