How to view and edit

the properties of an object

The properties of a map, table or column or any other ILWIS object shows you important information on the object. In fact, an object's Properties sheet is listing the information that is stored in an object's object definition file and that is relevant to the user.

Viewing the properties of an object may be very useful. You can see for instance the date and time and the description of the object, which other objects the current object is using (e.g. for raster maps the domain and georeference) and whether an attribute table is linked to a map or a domain. The properties sheet also shows whether the object is dependent or not, and whether a dependent object is up-to-date or not. Furthermore, you can easily update objects when they are not up-to-date any more, you can change the definition of calculated maps and calculated columns, break dependencies, etc. For more information, see Basic concepts : properties of objects.

Viewing properties of objects

To view the properties of an object (except columns):

Other methods are:

The Properties sheet of the selected object appears.

To view the properties of a column in a table:

The Column Properties dialog box of the selected column appears.

Handling properties of objects

For dependent maps, tables and columns, the most important features of a properties sheet or dialog box are invoked by pressing one of the following buttons that may appear in the Properties: Make Up-to-Date, Edit Definition, Break Dependency Link, Release Disk Space, Calculate.

  

Make Up-to-Date:

For dependent data objects of which the input data has changed: click this button to redefine the dependent output object. See also How to make dependent data objects up-to-date.

Edit Definition:

For dependent raster maps that are the result of a map calculation (MapCalculate), click this button to modify the map calculation formula by which this map was created. The definition of a dependent column that is the result of a table calculation (ColumnCalculate), can be directly edited in the Properties dialog box of the column. See also How to change the definition of a dependent data object.

Break Dependency Link:

For dependent data objects: click this button to break the dependency links between the current dependent object and the objects it depends on. After breaking dependency links of a dependent map, table or column, the map, table, or column becomes editable. See also How to break dependency links.

Release Disk Space:

For dependent data objects with a calculated data file: click this button to delete calculated data files. Only the object definition file that contains the expression by which the object is defined remains. See also How to release disk space.

Calculate:

For dependent data objects without a calculated data file: click this button to execute the expression by which this object was created and store the calculated data file on disk.

For more information, refer to Basic concepts : properties of objects or to the Property sheets.

Editing properties of non-dependent objects

For non-dependent objects, relations to other objects may be changed. You can for instance link another default representation to a domain, another georeference to a raster map, or link another coordinate system to a vector map, or change the domain of an object. Editing Properties is something for the more experienced user. Especially changing the domain of an object is only necessary in very specific cases and should never be done without a backup of your original map.

To edit the properties of a non-dependent object:

You can change the links to objects that the current object uses, such as domain, georeference, etc.

See also: