Test run of sparse vector package. Enter n : Uninitialized new vec v = [] Copy of v = [] Enter new entries of v: Dimension = Number of entries = Position: Entry: Position: Entry: Position: Entry: Now v = [(1:2),(3:4),(5:6)] w = [] After w=v, Now v = [(1:2),(3:4),(5:6)] Now w = [(1:2),(3:4),(5:6)] w==v: 1 w!=v: 0 v+w = [(1:4),(3:8),(5:12)] v-w = [] Enter i : After w*=2, w = [(1:4),(3:8),(5:12)] 3*v = [(1:6),(3:12),(5:18)] Now v = [(1:2),(3:4),(5:6)] v+w = [(1:6),(3:12),(5:18)] Now v = [(1:2),(3:4),(5:6)] v-w = [(1:-2),(3:-4),(5:-6)] Now v = [(1:2),(3:4),(5:6)] w/2 = [(1:2),(3:4),(5:6)] Now w = [(1:4),(3:8),(5:12)] -v = [(1:-2),(3:-4),(5:-6)] +v = [(1:2),(3:4),(5:6)] +w = [(1:4),(3:8),(5:12)] 2*v-w = [] Resetting w[1] to 99: w = [(1:99),(3:8),(5:12)] After w-=2*v, w = [(1:95)] v as an ordinary vector = [2,0,4,0,6,0,0,0,0,0]