Editing Tabular Data

1
Editing Tabular Data

• Francisco Olivera, Ph.D., P.E.
• Department of Civil Engineering
• Texas AM University

2
Overview

• Editing tabular data manually.
• Editing tabular data automatically.
• Creating new tabular data.

3
Edit Mode

• To make a table editable, in the Table GUI, click
  on the Table/Start Editing menu.
• The headers of all editable fields will display
  in standard (vertical) font instead of italics.

4
Editing Cells

• To edit individual table cells, click on the
  field header (it will change its color), then on
  the Edit tool, and then on the cell you want to
  edit.

5
Editing Fields

• To edit the values of all selected records of a
  table field, click on the field header (it will
  change its color), then on the Calculate button,
  and then fill the Field Calculator panel.
• The field calculator window can be filled with a
  string, a number, a mathematical expression or an
  Avenue expression, depending on the field type.

6
Adding Fields

• To add a new field to a table, click on Edit/Add
  Field menu, and then define the field you want to
  add.
• Fields can be numbers, strings, booleans or
  dates, and can have different widths and number
  of decimal digits (if numbers).
• The field values can be filled one-by-one with
  the Edit tool, or all-at-once with the Calculate
  button.

7
Adding Records

• To add a new record to a table, click on Edit/Add
  Record menu.

• Do not add records to Theme Attribute Tables,
  because they would not be associated to any
  feature shape. If a feature is to be added to a
  Theme, it should be added by editing the Theme
  from the View GUI.

8
Overview

• Editing tabular data manually.
• Editing tabular data automatically.
• Creating new tabular data.

9
Updating Attributes

• Some attributes need to be updated when the
  feature geometry is modified (i.e., splitting
  lines, merging lines, splitting polygons, merging
  polygons, etc.).
• Depending on the type of feature property an
  attribute describes, it can be updated in
  different ways
• Extensive properties (e.g., weight) refer to the
  entire feature, and have to be updated
  proportional to the area of the new polygons or
  length of the new lines.
• Intensive properties (e.g., density) refer to a
  unit area or length, and do not need to be
  updated.

10
After Splitting Features

• Attributes of the resulting features can be
• Blank
• Copy (default)
• Proportion
• Shape length (for lines)
• Shape area (for polygons)
• Shape perimeter (for polygons)

11
After Merging Features

• Attributes of the resulting lines can be
• Blank
• Copy (default)
• Proportion
• Add
• Average
• Shape length (for lines)
• Shape area (for polygons)
• Shape perimeter (for polygons)

12
Attribute Updating Rules

• To set the automatic attribute updating rules,
  before splitting or merging features, in the
  Theme Properties window, click on Editing, and
  then fill the Attribute Updating panel.
• Select the field to be updated, check the Single
  box, and set the Union and Split rules.

13
Updating Feature Geometry

• If a feature dataset does not have the Length or
  Area and Perimeter fields, or if they store
  incorrect values, they can be created or
  corrected automatically.
• Load the CRWR-Vector extension, make the Theme
  active, and click on the CRWR-Vector/Update
  Feature Geometry menu.

14
Adding Record Number

• Even if not displayed in the attribute table, all
  records of feature datasets have a unique
  identification number called Record Number. The
  record number can be automatically added to the
  attribute table.
• Load the CRWR-Vector extension, make the Theme
  active, and click on the CRWR-Vector/Add Record
  Number to Table menu. The Record number will be
  stored in a field called Recno.

15
Adding Coordinates

• The coordinates of point features and polygon
  feature centroids can be automatically added to
  the attribute table.
• Load the CRWR-Vector extension, make the Theme
  active, and click on the CRWR-Vector/Add XY to
  Table menu. The coordinates will be stored in two
  fields called X-coord and Y-coord.

16
Overview

• Editing tabular data manually.
• Editing tabular data automatically.
• Creating new tabular data.

17
Creating New Tables

• New stand-alone tables (i.e., not related to
  geographic data) can be created by clicking on
  the Tables icon in the Project window and then on
  the New button.
• The new table would be of dbf format and will
  have no fields or records.
• Fields, records and values have to be added
  one-by-one manually.