Using geographic operators in expressions – Pitney Bowes MapInfo Professional User Manual

Page 443

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Comment: The column "Shipped" is a logical column. It contains "T" for true, or yes, and "F" for false,
or no. When an order is shipped, it is marked "T". Otherwise, it is not shipped. For orders that are shipped,
expression 28 evaluates to true. For orders not shipped it evaluates to false.

English: All that have not shipped.

1. Str$(Shipped)="F"

2. Not Shipped

Using Geographic Operators in Expressions

MapInfo Professional has several geographic operators. Use them to select objects on the basis of their
spatial relationship to some other object. MapInfo Professional has a special keyword you use with
geographical operators: "obj" or "object". This keyword tells MapInfo Professional that it has to get values
based on the graphical objects in the table rather than the tabular data.

The geographic operators go between the objects being specified. Select the geographic operators from
the Operators menu. Here are the geographic operators:

Object A Contains object B if B's centroid is anywhere within A's
boundary.

Contains

Object A Contains Entire object B if B's boundary is entirely within
A's boundary.

Contains Entire

Object A Contains Part object B if B's boundary is partly within A's
boundary.

Contains Part

Object A is Within object B if its centroid is inside B's boundary.

Within

Object A is Entirely Within object B if A's boundary is entirely within
B's boundary.

Entirely Within

Object A is Partly Within object B if A's boundary is partly within B's
boundary.

Partly Within

Object A Intersects object B if they have at least one point in
common.

Intersects

"Contains Part" and "Partly Within" are exactly equivalent to "Intersects"-these are all treated the same
way by MapInfo Professional, so the standard syntax "Intersects" is almost universally used.

"Contains" and "Within" are concerned only with objects' centroids.

"Contains Entire" and "Entirely Within" are concerned with the area covered by a region object; the
location of the centroid does not matter. See examples in Using Geographic Operators in Expressions
in the Help System.

443

MapInfo Professional User Guide

Chapter 17: Specialized Topics in MapInfo Professional

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