Data set member attribute definition 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 data set member.

These files (also called field definition files) are stored in the same sub-directory as the dataset member definition file (<dataset directory name>.def). The filenames are also specified in this file, except in cases where there are e.g. many similar themes (for instance separated in time). In such cases a file named alias.fld may be used as valid for all themes in a data set folder, and the data set member definition file is not necessary. The format of the files differs depending on whether the data set member is a theme or a table.

The following shows the contents of the aari_riv.fld file (theme format):

"Fieldname","Alias","Display","LUT-File","Description"

"Field name aliases and corresponding LUT files for Observation locations for AARI river data",,,,

"Riv_No_","Riv.No.","Y","","AARI river ID number"

"River","River","N","","Name of river"

"Obs__Loc","Observation Location","N","","Name of observation location"

"Dst__to_Mo","Distance to river mouth (km)","Y","","Distance from observation location to river mouth (km)"

"Watshd_Are","Watershead Area (km2)","Y","","Watershead Area (km2)"

The following shows the contents of the riv_runoff.fld file (table format):

"Fieldname","Alias","Description"

"Field name aliases and descriptions for riv_runoff.dbf",,

"Riv__no_","Riv.No.","River ID number"

"Month","Month",""

"Ll","Lower limit","Lower limit (kmł)"

"Lu","Upper limit","Upper limit (kmł)"

"LL_UL","Range","Lower limit - Upper limit"

"N","No. of observations","No. of observations"

"Fr","Frequency of occurrence (%)","Frequency of occurrence (%)"

The first line is common to all these files and must not be changed. The second line is a comment line identifying the data set member. The four/two commas ending the line must be there. The last two lines specify the descriptive attributes suitable for classification with a pre-defined default legend. The first column ("Fieldname") specifies the physical (storage) field names in the attribute table of the theme. The next column ("Alias") specifies a descriptive name for each attribute for use as field name aliases. As the dBase files cannot use field names longer than 10 characters, this utility enables using longer field name aliases when displaying field names to a user. The last column may include a short description of the contents of each field. This description is used when INSROP GIS generate metadata for a data set member.

The two additional columns in the theme format, are used to define whether the contents of a field are intended for display using the Theme-'Display attribute' menu option in the Views interface. The fourth column ("LUT-file") specifies the name of the attribute value definition file (look-up-table) associated with each attribute (if one exists). This column may be empty, in which case default symbols and random colours will be employed in the legend classification.

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