The operation creates a subgraph and computes a line diagram from the values of the field. The indexes of the data records are placed to x-axis, and their values are presented in y-axis. If the subgraph identified by <index> does not exist, first the operation creates a new one.
Example (ex7.22): Two fields "crim" and "zn" are described by line diagrams in the lower subgraph. The field "age" is displayed in the upper subgraph.
NDA> load boston.dat NDA> mkgrp grp1 NDA> ldgrv grp1 -inx 0 -f boston.crim -co red NDA> ldgrv grp1 -inx 0 -f boston.zn -co green NDA> ldgrv grp1 -inx 1 -f boston.age -co blue NDA> show grp1
