Upon completion of the editing, the next task is "tagging". In this phase, digital 
vector data is linked with analog attribute information (codes) by means of 
interactive graphic techniques. For the hypsography overlays, tagging of the 
contours with height values is performed with the aid of several commands (semi- 
automatically) that facilitate the tagging process. 
4. EDITING 
Editing refers to the process of detecting and correcting the errors made at the 
various stages of data caputre (e.g. digitizing), and supplementing the data with 
locational and alpha-numeric information. This assures the completeness and the 
correctness of the digital data. Editing also includes manipulation of the data to 
meet the specifications of the end product (e.g. generalization, line smoothing, 
cartographic features displacing due to symbolization) and to ensure that quality 
standards have been met. 
In the Surveys and Mapping Branch, several modes of editing are in use, namely: 
interactive, automatic (batch) and semi-automatic editing. 
Regardless of the mode of editing, interactive display and editing plays an 
important role in the data capture phase. Interactive display and editing is 
performed using a computer graphics display terminal and utilizing several 
interactive editing functions. These functions include: display control, graphic 
editing, attribute data editing (tagging/coding) and data structure editing. 
The display control functions are used to select, display and manipulate file data. 
For example, the "WINDOW CONTROL" functions may be used to control the 
amount of data to be displayed and to define the limits of a file window to be 
viewed. "VIEW CONTROL" functions in conjunction with the above allowing for 
the scaling, rotation, and shifting of the data viewed. "DATA CONTROL" 
functions allow the operator to display file contents on the screen in graphic, 
alpha-numeric, or a fully numeric format. 
Graphic editing functions allow for the updating of file contents by creating, 
deleting or changing the graphic elements. Some of the most common commands 
are: 
create Copy delete/hide 
modify move cut 
drop change replace 
scale rotate transform 
Attribute data editing refers to the editing of non-locational, non-topological data 
attached to the feature. The following commands are used to: 
- create and add new attributes to an existing feature; 
- Copy data from one existing attribute to another; 
- locate attribute values; 
- change attributes in existing feature; 
- correlate a graphic and attribute data base; and 
- delete feature records form the data base. 
518 
CC