Raja Yoga or Yoga of Self-Control. Raja means “royal”. This path is considered to be the King of Yoga and this may be due to the fact that most of its practitioners are members of religious and spiritual orders. Raja Yoga is based on the teachings of the Eight Limbs of Yoga found in the Yoga sutras.
A Raja Yogi sees the self as central, and as such, respect to oneself and for all creation are vital to this path. They achieve self-respect by first learning to be masters of themselves.
If you wish to learn discipline, then Raja Yoga would perfectly suit that need.