Goal: Query the mesh information for the active selection.

Code:

# Macro to demonstrate how to query mesh information for the active selection

meshData = DataModel.MeshDataByName("Global")
sel=ExtAPI.SelectionManager.CurrentSelection
refIds = sel.Ids

# check that current selection is nodes
if sel.SelectionType == SelectionTypeEnum.MeshNodes:
    print "%s Nodes Selected" % (refIds.Count)
    for meshId in refIds:
        node = meshData.NodeById(meshId) 
        print "Node %s, X = %s, Y = %s, Z = %s" % (meshId, node.X, node.Y, node.Z)
else:
    print "Selection is not made of nodes"