An ARB is a portion of space bounded by 4, 5 or 6 plane faces. Its use is rather complicated and is now superseded by the availability of infinite planes (XYP, XZP, YZP and PLA). For completeness, however, a description of input will be reported here. Assign an index (1 to 8) to each vertex. For each vertex, give the x, y, z coordinates on 4 cards (8 cards in high-accuracy body fixed format), with 6 numbers on each card (3 numbers per card in high-accuracy fixed format): V1_x, V1_y, V1_z, V2_x, V2_y, V2_z, V3_x, V3_y, V3_z, V4_x, V4_y, V4_z, V5_x, V5_y, V5_z, V6_x, V6_y, V6_z, V7_x, V7_y, V7_z, V8_x, V8_y, V8_z The vertices not appearing in face descriptions are ignored, but eight must always be supplied. The above vertex cards are followed by one card describing the faces (two cards in high-accuracy fixed format). Each face is described by a four-digit number in floating point format, such that each digit gives the indices of the three or four vertex points of that face. These indices must be entered in the same order for each face (i.e. all clockwise or all counterclockwise). When the number of the faces is less than 6, the remaining face description(s) must be zero, and must appear at the end of the list. If a face has three vertices, the omitted position may be either 0 or a repeat of one of the other vertices. An ARB definition extends over 5 cards in default fixed format, or over 10 cards in high-accuracy body fixed format. Example in default fixed format:*...+....1....+....2....+....3....+....4....+....5....+....6....+....7..ARB 5 -44.2 -36.5 3572.0 -44.2 -33.5 3572.0 -37.1 -31.0 3572.0 -37.1 -39.0 3572.0 -44.2 -36.5 0.0 -44.2 -33.5 0.0 -37.1 -31.0 0.0 -37.1 -39.0 0.0 1234. 1562. 5876. 1485. 4378. 6732.* (a right prism of trapezoidal base, of height 3572 cm parallel to the* z axis)The same example in high-accuracy body fixed format:*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+.ARB 5 -44.2 -36.5 3572.0 -44.2 -33.5 3572.0 -37.1 -31.0 3572.0 -37.1 -39.0 3572.0 -44.2 -36.5 0.0 -44.2 -33.5 0.0 -37.1 -31.0 0.0 -37.1 -39.0 0.0 1234. 1562. 5876. 1485. 4378. 6732. The same, in free format: ARB oddbody -44.2 -36.5 3572.0 -44.2 -33.5 3572.0 -37.1 -31.0 3572.0 -37.1 -39.0 3572.0 -44.2 -36.5 0.0 -44.2 -33.5 0.0 -37.1 -31.0 0.0 -37.1 -39.0 0.0 1234. 1562. 5876. 1485. 4378. 6732.