# Simplify Curves

Simplify one or more curves by changing the number of control points and inverting their sequence, joining multiple curves, or by applying an arc length parametrization.

1. On the Geometry ribbon, select the Simplify tool.

Note: The tool may be hidden in the dropdown menu. To access the dropdown menu, you can do one of the following:
• Select at the lower right corner of the currently displayed tool.
• Click and hold the currently displayed tool.
The guide panel appears. By default, the Curves tab is open.

2. Next to Curves, the Select button is active. Select one or more curves.
By default, the curve is simplified using the Fit by Tolerance method and, if you selected multiple curves, they are joined.
3. Select a method:
• Fit By Tolerance: By default, the simplified curve fits the Modeling tolerance defined in the Preferences. To define a custom tolerance, turn on Custom Tolerance, and then enter the Tolerance. Increase the tolerance to decrease the number of points.
• Fit By Number of Points: Type the number of Control Points. You can also enter the Degree of the curve.
• Reduce Points: Only applies to NURBS curves. Reduce the number of control points in the input curve. You can use Fit By Tolerance to create an approximation of the original curve with fewer points, but you should use the Reduce Points method to collapse control points on the original curve.By default, the simplified curve fits the Modeling tolerance defined in the Preferences. To define a custom tolerance, turn on Custom Tolerance, and then enter the Tolerance. Increase the tolerance to decrease the number of points.
• Arc Length Parametrization: Parametrize the curve by arc length.
4. In the guide panel, select the Display tab to configure the display:
Table 1.
Option Description
Control Points Display the control points.
Input Curves Display the input curves in orange. The simplified curve is displayed in blue.
Show Max Deviation Display a red point where the distance between the input curves and the simplified curve is the greatest.

The Max Deviation indicates the maximum distance between the input curves and the simplified curve.

Input/Output/Reduction (%) The first number corresponds to the number of control points on the original curve, the second number corresponds to the number of control points on the simplified curve, and the last number corresponds to the percentage reduction in the number of points.
5. Right-click and mouse through the check mark to exit, or double-right-click.