Aggregating graph structures

A computer program product for making a computer function as a display apparatus adapted to display a plurality of graph structures, each of which is made up of a plurality of elements, by aggregating the plurality of graph structures into a single graph structure, wherein the program product comprises a computer readable storage medium having program code embodied therewith, the program code readable and executable by a processor to perform a method comprising:

• acquiring a plurality of graph structures;
• distinguishing the plurality of elements between unchanged elements that have not changed in the plurality of graph structures and changed elements that have changed with transition between/among the plurality of graph structures;
• aggregating the plurality of graph structures;
• displaying the aggregated graph structure such that the unchanged elements and the changed elements will be identifiable;
• acquiring a graph structure that contains nodes and edges as individual elements of the plurality of elements;
• acquiring the plurality of graph structures at a plurality of time points in a time series;
• and
• contracting two or more elements in the aggregated graph structure into a single contracted element, wherein the aggregated graph structure is displayed as the single contracted element instead of the two or more elements.

A display apparatus adapted to display a plurality of graph structures by aggregating the plurality of graph structures into a single graph structure, wherein each of the graph structures is made up of a plurality of elements, and wherein the display apparatus comprises:

• an acquisition hardware unit adapted to acquire a plurality of graph structures;
• a distinguishing hardware unit adapted to distinguish the plurality of elements between unchanged elements that have not changed in the plurality of graph structures and changed elements that have changed with transition between/among the plurality of graph structures;
• an aggregating hardware unit adapted to aggregate the plurality of graph structures;
• and
• a display hardware unit adapted to display the aggregated graph structure such that the unchanged elements and the changed elements will be identifiable, wherein the display hardware unit displays the aggregated graph structure such that the changed elements, once deleted at plural time points and then generated again, are identifiable.