how to use voronoi function in for k-means clustering....???

i m apply k-means clustering method for clustering but i don't know how voronoi function work because i have data like following..

inputs=[0.0001 0.00123
0.0001 0.00123
0.0001 0.01123
0.0001 0.00323
0.0001 0.00423
0.0001 0.05123
0.0001 0.60123]

this type of 1000 data now how can i apply voronoi function i do not know what range should be use that i can get perfect answer please help me and give idea about this function...