geometry_line index x_0 y_0 z_0 x_1 y_1 z_1 radius

This data item defines a line in space. Other data items can check if nodes are located on this geometry. Coordinates of the end points are denoted by x_0, etc.. In 1D, only the $x$-coordinates should be specified, etc.. All node within a distance radius are considered to be part of the line.

In the example, a line in 2D space is defined and is used by a convection_geometry record (nodes located on the line will convect heat)

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geometry_line 2 1. 0. 1. 1. 0.01
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group_condif_convection_geometry 0 -geometry_line 2
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