Go to ET GeoWizards 12.x User Guide

Calibrate routes with points

Adjusts route measures with existing points using measure information stored as attributes in the Point Attribute Table or the M values of pointM dataset. The calibration process inserts new vertices to the routes in the places where the calibration points intersect the routes. The measure value of these vertices is set to the measure value of the corresponding point. The measures of the existing vertices is adjusted according to the interpolation/extrapolation option selected and the adjustment method selected.

Inputs:

• A PolylineM feature layer - to be calibrated
• Route Identifier field
• A Point or PointM feature layer - to be used for calibration
• Point Route Identifier field
• Point Measure field (only if the measures are to be taken from a field)
• Search tolerance - only the points that are closer to the route than this tolerance will be used for calibration
• Interpolation/Extrapolation options
• Adjustment method
• Output Spatial Reference

Output:

• A PolylineM feature class. The measures are adjusted based on the point dataset and the options selected by the user

Interpolation options: 

      Three options are available. They can be used in any combination

• Extrapolate before calibration points - the measures of the preexisting vertices before the first calibration point will be adjusted
• Interpolate between calibration points -  the measures of the preexisting vertices between the first and last calibration points will be adjusted
• Extrapolate after calibration points - the measures of the preexisting vertices after the last calibration point will be adjusted

	Original route and Calibration points
	All options used for calibration. The measures of the vertices before, between and after the calibration points are adjusted
	Only "Interpolate between" option used. The vertices before and after calibration points preserve their original measures

Adjustment methods:

• Shortest path distance - the distance between the measure points is used to establish the calibration ratio. Then this ratio is applied to the preexisting vertices based on their distance to the calibration points.
• The existing measure distance - The measures of the calibration points are calculated based on the existing measures. This measures are compared to the new measures to establish the calibration ratio. Then this ratio is applied to the preexisting vertices based on their M values points.

Notes:

• Spatial Gaps: In many cases a route consists of disjoined parts A road for example that have the same name on both sides of a river might be represented by a single route. For such cases the user has to specify how the spatial gaps between the disjoined parts of the route will be handled when calculating the measures. 

	Ignore Spatial Gaps option selected - Continuous measurements
	Ignore Spatial Gaps option not selected - The gap distance incorporated into the measures. The straight-line distance between the disjoined nodes added to the measures

• The user can specify output spatial reference that is different from the projection of the input dataset. The Output Spatial Reference must have the same geographic coordinate system as the input dataset and the calibration points dataset