Transfiguration you have to get it exactly right, transfiguration is more scientific. Transfiguration was a very systematic, exact magical discipline, working best for the scientifically -inclined mind and as such it was deemed ‘’ very hard work’’ (especially compared to charms, which afforded a much larger margin for personal creativity) . Also ‘’ when transfiguring , it is important to make firm and decisive wand movements. Do not wiggle or twirl your wand unnecessarily, or the transfiguration will certainly be unsuccessful’’ as stated by Emeric Switch in A Beginner’s Guide to Transfiguration. There were a number of factors a wizard had to take into account when carrying out transfiguration spells. The intended transformation (t) was directly influenced by body weight (a) , viciousness (v) , wand power (w), concentration (c) and a fifth unknown variable (Z), as described by the following mathematical formula (as taught to first-years at Hogwarts School of Witchcraft and Wizardry).