R310

R310 / 1c:1c-1

Partitioned Box is split below zero or one Partitioned Box

Partitioned Box is split above zero or one Partitioned Box

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A Compartment Box is a rectangular area within or encompassing, in the case of an Envelope Box, the Title Block Pattern.

It can be divided by a horizontal or vertical line into two smaller Partitioned Boxes.

In the case of a vertical split, the Partitioned Box is vertically 'above' the lower counterpart. It's obvious in this case because the y coordinate of the lower left corner is greater than that of the lower Partitioned Box.

In the case of a horizontal split we use the same concept, but the Partitioned Box to the right is considered 'above' since its lower left corner x coordinate is greater.