Tuflow and estry manual Version 3

3.13.3Free-form Tabular Input (1d_ta Layers)

Tables of cross-section profiles, cross-section hydraulic properties, nodal surface areas and bridge loss coefficients are accessed using links within a 1d_ta GIS layer. This allows these data to be entered in a free-form comma or space delimited format (as opposed to the fixed field formats) using .csv files that can be managed and edited in spreadsheet software such as Microsoft Excel.

Table 4 .13 describes each of the attributes and the method for determining which data to extract from the source file. Using the Column_1 attribute, several tables can be located in the one source file if desired.

Read MI Table Links defines the 1d_ta layer(s) to be used for linking tabular data to nodes and channels. The method for linking is as follows:

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  Lines and polylines (unlimited vertices as of Build 2002-10-AA – previously two or three vertices only) are used to link to channels. A two-point line must intersect or cross the channel line – it does not have to snap to a vertex on the channel line. If the two-point line crosses more than one channel, the channel that is closest to the mid-point of the line is selected. Three or more vertex lines must have one of the vertices snap to a vertex on the channel line and are given preference over any two-point line that crosses the channel line.
  
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  Points are used to link to nodes. The point must be snapped to a node (or channel end if automatically creating nodes).
  
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  Other objects are not used.
  

This feature was incorporated at Build 2002-08-AC and was further improved for Build 2003-03-AA during which the Flags attribute was split into two attributes: Type and Flags as described in Table 4 .13.
Table 4.13 1D Table Links (1d_ta) Attributes