The External Format Specification (EFS) is a way of describing to the computer how to interpret data coming in from ASCII files. The computer reads in the file and parses it according to the EFS to create features in Terrain.
EFS uses the following terminology:
Features
The term feature refers to a set of 'associated' x,y,z coordinate points, for example a contour line is a feature. In the Terrain module many operations apply to Features (see Features for more information).
Records
The term record refers to an entry in the file containing a single x,y,z coordinate point. Additional information such as comment, or ID number can be also included in a record.
Fields
The term field refers to the specific items that make up a record. For example the x coordinate is a field.
Example 1
External File contains:
Features
Id
X
Y
Z
Records
feature 1
feature 2
feature 3
1
1
1
2
2
2
3
3
3
3
362.8
363.7
364.3
372.5
372.9
376.8
392.8
383.7
394.1
398.1
927.4
928.2
929.6
931.0
929.1
927.3
947.4
948.2
948.6
949.9
1700.0
1700.0
1700.0
1750.0
1750.0
1750.0
1800.0
1800.0
1800.0
1800.0
record 1
record 4
record 7
File consists of 3 contour features. The first two features contain 3 records and the 3rd feature contains 4 records. Each record contains 4 fields (id, x, y, z).
Example 2
External File contains:
Features
X
Y
Z
Records
feature 1
feature 5
feature 10
1362.8
1363.7
1364.3
1372.5
1372.9
1376.8
1392.8
1383.7
1394.1
1398.1
2927.4
2928.2
2929.6
2931.0
2929.1
2927.3
2947.4
2948.2
2948.6
2949.9
2701.5
2706.0
2703.2
2711.4
2721.8
2721.1
2727.0
2718.4
2715.8
2716.0
record 1
record 5
record 10
This file consists of 10 features (random points). Each feature consists of 1 record. Each record contains 3 fields (x,y,z).
