Constructing a Curve

Construct Curve dialog box

Two types of constructed curves (Independent Curves and Dependent Curves) are available in PC-DMIS. The following table displays the two curves along with their necessary inputs. All curves require a set as input. The set can be a measured set, a constructed set, or a scan. The input set must contain at least four features (or input points in the case of a scan).

CONSTRUCT FEATURE TYPE

SYMBOL IN EDIT WINDOW

#  OF INPUT SETS

INPUT #1:

COMMENTS

Dependent Curve

DEPENDENT

1

Set containing at least 4 inputs

The Curve updates as the input changes.

Editing a curve changes a dependent curve to an independent curve.

Independent Curve

INDEPENDENT

1

Set containing at least 4 inputs

Uses the input feature for construction only. You can manually edit control points of the curve.

The Edit window command line for a sample Curve Construction using a dependent curve type would read:

feature_name=FEAT/CURVE, DEPENDENT, num_control_points, num_input_feats, thinning_parameter

CONSTR/CURVE,INPUT_TYPE, input_id

For an independent curve type the Edit window command line would read:

feature_name=FEAT/CURVE, INDEPENDENT, num_control_points, num_input_feats, thinning_parameter

CONSTR/CURVE,

num_control_points = This is the number of control points that define the curve. More control points allow the curve to more closely pass through the features, but too may cause unexpected behavior

num_input_feats = This is the number of features that the curve is attempting to fit.

These two parameters are not editable in the Edit window.

input_id = This is the ID of the set containing the features to be fitted.

thinning_parameter = This is described in the "Thinning Parameters" topic described below.

The actual Edit report displays in all capital letters.

More:

Constructing a Dependent / Independent Curve