Table 3: Geometric connections and feature coding.

ClassForm features

I {I1. same forms arranged in neat rows, I2. same forms but changeable alignment, I3. form changeable but in neat rows, I4. form changeable and changeable alignment}
J {J1. large function keys, J2. symmetric dispersion function keys}
K {K1. near to 0, K2. small R angle, K3. middle R angle, K4. big R angle, K5. semirounded}
L {L1. two, L2. three, L3. four, L4. five, L5. six and more}
M {M1. flip, M2. slide, M3. straight, M4. rotation}
N{N1. by cover, N2. by frame, N3. by screen}