Returns an array of node information, where each array element is the unique number of a node.
The number of elements in the array can be determined by NodeInfo.getNumAMPs().
The array elements map one-to-one with the array elements from NodeInfo.getAMPIds(). For example, the second array element from NodeInfo.getNodeIds() is the node number for the AMP in the second array element from NodeInfo.getAMPIds().
Node numbers occur in ascending order and each node number is repeated for the total number of AMPs on that particular node.