There is a way to accomplish this, but it is not easy. It is even more difficult if you attempt to do it by hand. However, it will be a while before I release the next version of my program, so I'll take you through the steps.
First you write down all the Stats for all levels between level 5 and 15. Then you plug into the Stat formula IVs 0 through 31. The formulas to do this:
HP: Math.Floor((((base * 2 + iv + Math.Floor(ev / 4)) * level) / 100) + 10 + level)
Non-HP: Math.Floor(((base * 2 + iv + Math.Floor(ev / 4)) * level / 100 + 5) * personality)
(personality can be either .9, 1.0, or 1.1)
Start at 0. As soon as you calculate a Stat for a level that doesn't match any one of the levels of the actual pokemon, that IV must be thrown out. Then go onto the next. In the end, you will end up with the IV for each stat being one of two numbers, or, if you get lucky, you will end up with only 1 IV at the end (making the next part easier).
This is where the tricky part comes in. Now you must figure out the type of hidden power your pokemon has. Hopefully, everyone knows how to go about doing this (Kecleon being the easiest way). Since each stat has only 2 choices at most, you can only match the specific HP Type once with any given pattern of IVs. Once you go through a huge loop to match the existing ivs with the ivs you would get for that specific HP Type, you will know the exact IVs.
First you write down all the Stats for all levels between level 5 and 15. Then you plug into the Stat formula IVs 0 through 31. The formulas to do this:
HP: Math.Floor((((base * 2 + iv + Math.Floor(ev / 4)) * level) / 100) + 10 + level)
Non-HP: Math.Floor(((base * 2 + iv + Math.Floor(ev / 4)) * level / 100 + 5) * personality)
(personality can be either .9, 1.0, or 1.1)
Start at 0. As soon as you calculate a Stat for a level that doesn't match any one of the levels of the actual pokemon, that IV must be thrown out. Then go onto the next. In the end, you will end up with the IV for each stat being one of two numbers, or, if you get lucky, you will end up with only 1 IV at the end (making the next part easier).
This is where the tricky part comes in. Now you must figure out the type of hidden power your pokemon has. Hopefully, everyone knows how to go about doing this (Kecleon being the easiest way). Since each stat has only 2 choices at most, you can only match the specific HP Type once with any given pattern of IVs. Once you go through a huge loop to match the existing ivs with the ivs you would get for that specific HP Type, you will know the exact IVs.