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.
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