A summary of the relationships between the various internal coordinate systems is illustrated in figure , where the length of the bars correlates with the dimensionality of the coordinate space. As the name implies, the nonredundant internal coordinate The full redundant internal coordinate space q (dark blue) is projected into the smaller nonredundant space q (green) with the projection matrix N. This space is further split into the constrained space (yellow) and the unconstrained space q (red), which are obtained from q with the projection matrices P and Q, respectively.