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Data set member attribute value look-up-files

The main purpose of these files is to automate legend classification using the same symbols for all similar data themes, but they also serve as documentation of attributes and range of attribute values of each theme.

These files are stored in the same sub-directory as the attribute definition files. The filenames are also specified in this file. These LUT files differ in content depending on whether the theme has point, line or polygon data. The following shows the first two lines for each of the three LUT-file formats:

Point data:

"Value","Label","Symbol#","Color","Size"

"Look up table for aTheme point data: anAttribute",,,,

Line data:

"Value","Label","Symbol#","Color","Width"

"Look up table for aTheme line data: anAttribute",,,,

Polygon data:

"Value","Label","Symbol#","Color","OlWidth","OlColor","BgColor"

"Look up table for aTheme polygon data: anAttribute",,,,,,

The first line is common to all these LUT-files of each type and must not be changed. As seen, the first four columns are equal for all types, while the remaining column(s) differ, as they define the size and look of the chosen symbol. The second line is a comment line identifying the data set member and attribute. The commas ending the line must be there. The next lines in the files will specify how each attribute value should be displayed. The first column (Value) specifies a legal value that may be included in the attribute field of this data set member. The second column ("Label") specifies what this value represents. The label will also be used in the legend to identify the symbol for each attribute value.

The third column ("Symbol#") is the number of the symbol in the ArcView symbol palette (where 0 is the number of the first symbol in the list). For point data the symbol# identifies a symbol in the Marker symbol palette, for line data the symbol# identifies a symbol in the Pen symbol palette, while for polygon data the symbol# identifies a symbol in the Fill symbol palette. The symbol# column must not be empty.

The fourth column ("Colour") specifies the name of the colour to be used for the symbol. This column may be empty (,,), in which case a random colour will be used. The colour names are similar to UNIX colour name table, and includes 738 colour names defined by their RGB values. Appendix C list the contents of the AVENUE script specifying the colour names. To get a transparent fill, the colour must be specified as "Transparent".

The next columns are optional. The fifth column specifies a size property of the symbol. For point data the fifth column ("Size") specifies the marker size in pt., while for line data the fifth column ("Width") specifies the line width in pt. For polygon data the fifth column ("OlWidth") specifies the outline width in pt., while the sixth ("OlColor") and seventh ("BgColor") columns defines the outline and background colour respectively. To achieve a polygon fill without an outline, the outline colour must be specified as "Transparent".

As an example, the following shows the first four and the last lines of the dnlntype.lut file:

"Value","Label","Symbol#","Color","Width"

"Look up table for DCW DNNET line data: Dnlntype",,,,

1,"Stream, river, channelized river",0,"lightblue",

2,"Inland water body shoreline",0,"lightblue",

...

9,"Tile boundary or null arc",,"Transparent",

The main purpose of these files (and the attribute definition files) is to automate legend classification using the same symbology for all similar data themes, but they also serve as documentation of attributes and range of attribute values of each theme.