Cylindrical coordinate directions are indicated using the values CR, CA, andCZ. Spherical coordinate directions are indicated using the values SB, SA, and SR. The sign is required. See Figure 2 (page 19).
The cylindrical and spherical coordinate directions are not constant but vary with angular position. The coordinate directions do not change with the lineal coordinates. For exam ple, +SR defines a vector directed from the origin to point P.
Note that the coordinates Z and CZ are identical, as are the corresponding coordinate directions. Similarly, thecoordinates CA and SA and their corresponding coordinate directions are identical.