ILWIS objects

Data objects

ILWIS data objects are maps, tables and columns; that is the GIS material to work with. Data objects can be created, edited, displayed, etc., and most important operations can be performed on them. Except for columns, data objects in the current directory are listed in the Catalog by a name and an icon.

Data objects are:

	raster maps	(containing pixels)
	polygon maps	(containing closed area features)
	segment maps	(containing line features)
	point maps	(containing point features)
	tables	(containing columns)
	columns	(not listed in Catalog)

Each data object (a map, table or column) has a domain in which the valid IDs, Class names, values etc. of the object are defined. Other service objects that a data object may need are for instance a representation, a georeference, or a coordinate system. For more information on relations between ILWIS objects, see Appendices : relations between ILWIS objects.

In ILWIS 3, object names comply with Windows long file names.

In object names, any character may be used except \ / : * ? < > | "
The maximum length of an object name is 255 characters including the full path.

Furthermore, it is not allowed to use % in any ILWIS object name.

In dialog boxes, long object names can be used freely.

On the command line and in scripts however, object names must be enclosed by single quotes e.g. 'My Map'.mpr when the object name:

starts with a digit from 0 to 9,
starts with or contains one or more spaces, or
starts with or contains any of the following special characters ` ~ ! @ # $ ^ & ( ) - + = [ ] { } ; ' , .