I can't find it!

Alright you guys i need your help! There is this potato like rooter that i eat a lot of I know the name in Haitian creole and i cant find the english translation for it so its been difficult to find the nutritional information. Some people call them garnet yams But when i google that i get sweet potatos It has a dark purple reddish skin, very strachy, Very white on the inside, with a sweet taste to it anyone know the name?