# Points To Points Centering Block

The block computes the transform that maps the GroupB points to their corresponding GroupA points.

## General Information

Class name: PointsToPointsCenteringBlock

Namespace: Cognex.Designer.AlignPlus.Alignment

Assembly: Cognex.Designer.AlignPlus.Alignment.dll

## Inputs

Name | Type | Description
--- | --- | ---
GroupA Points | List<CogAlpsPointFeature> | Point features representing the target position of the part
GroupB Points | List<CogAlpsPointFeature> | Point features representing the current position of the part *Only shows when Accept Multiple GroupB Point Sets property is set as false.
GroupB Points List | List<List<CogAlpsPointFeature>> | A list of GroupB Points representing multiple run time parts' current positions. *Only shows when Accept Multiple GroupB Point Sets property is set as true.

## Outputs

Name | Type | Description
--- | --- | ---
Distances between GroupA and Transformed GroupB Points | CogDictionary | Average distances between Transformed GroupB points and GroupA points.
GroupA from GroupB Transform | CogTransform2DLinear | The transform that maps the points of GroupB to points of GroupA. *Only shows when Accept Multiple GroupB Point Sets property is set as false.
GroupA from GroupB Transforms | List<CogTransform2DLinear> | A list of transforms that maps GroupB point sets to GroupA point set. *Only shows when Accept Multiple GroupB Point Sets property is set as true.
Transformed GroupB Points | List<CogAlpsPointFeature> | GroupB's Point features after applying transform, theoretically it should be very close to Group A line features

## Properties

Name | Type | Description
--- | --- | ---
Accept Multiple GroupB Point Sets | Boolean | True: this block will compute multiple transforms that map each GroupB point set to Group A point set. False: this block only computes one transform that map one GroupB point set to Group A point set.
Degrees of Freedom to Compute | Constant | Degrees of Freedom taking into consideration while calculating GroupB to GroupA linear transform