Method of diagnosing errors off-line in pipe specification files of a computer-aided graphics system

Claim 1

An off-line method for aiding updating of a graphical system for producing in a plane having two-dimensional pipeline coordinate axes, a planar, axonometric representation of a three-dimensional pipeline in which material and non-material aspects of piping elements of said pipeline are associated with a multibit digital code representative of a series of workpoints compatible for use within a digital computer system, said workpoints being paired into overlapping sets, each set containing dominant and subservient points having known coordinates with respect to intersecting axes X, Y and Z, and being identified in relative three-dimensional coordinates by a distance (d) between points and values of angles of a straight line intersecting them as related to orthogonal planes of reference, comprising: (A) by means of said digital computer system, storing and sorting pipe specification information about said pipeline both as (i) machine readable data words or portions of words, and (ii) as a function of field locations within a preselected data format for operation within said system; (B) by means of said digital computer system, inputting off-line updated pipe specification data in said format on an iterative basis; (C) by means of said digital computer system, comparing said updated pipe specification data with said stored and sorted pipe specification data; and (D) by means of said digital computer system, indicating correctness of said compared data whereby errors associated with said updated pipe specification data, can be determined and then corrected, off-line.