Number types

• real (float) R: x
• complex C: x + yi, i² = -1
• dual D: x + yε, ε² = 0
• split-complex S: x + yj, j² = 1
• quaternion H: w + xi + yj + zk, i² = j² = k² = ijk = -1
• tessarine T: w + xi + yj + zk, ij = ji = k, i² = k² = -1, j² = 1
• split-quaternion: w + xi + yj + zk, ij = ji = -k, i² = -1, j² = k² = 1