15. The method of claim 11, wherein said determining differences includes matching said first plurality of objects of said first graphical program with said second plurality of objects of said second graphical program.
15. The method of claim 11, wherein said determining differences includes matching said first plurality of objects of said first graphical program with said second plurality of objects of said second graphical program. 31. The method of claim 15, wherein said matching produces a resolved match matrix, wherein said resolved match matrix comprises matching information regarding matches between said first plurality of objects in said first graphical program and said second plurality of objects in said second graphical program; wherein said determining differences between said first graphical program and said second graphical program comprises: grouping objects which have exact matches with connectivity matches into exact matching connected components using said matching information; grouping remaining objects to produce non-exact matching connected components wherein said grouping remaining objects produces a first list of non-exact-matching connected components and produces a second list of non-matching connected components; matching said first and second lists of non-exact matching connected components, wherein said matching said first and second lists of non-exact matching connected components includes finding common objects in said first and second lists of non-exact matching connected components, wherein said matching said first and second lists of non-exact matching connected components produces second matching information; merging said first and second lists of non-exact matching connected components using said second matching information, wherein said merging produces a composite non-exact matching connected component list; storing corresponding non-exact matching connected components in a result data structure; comparing matching objects in corresponding non-exact matching connected components to determine additional object differences; storing said additional object differences in said result data structure.