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XYZ points

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Overview

XYZ points are use do define discrete geo-referenced information. This information is stored associating X and Y coordinates to an attribute. Examples of applications of these items are: bathymetric or topographic surveys, water quality analysis results, etc.

XYZ Points file

XYZ Points items are stored in an ASCII text file. The default extension for XYZ Points files in MohidGIS is *.xyz. This file is organized in blocks, each containing the coordinates for a certain attribute. One block is defined by the following keywords: <begin_xyz> and <end_xyz>. Note that these keywords are case sensitive. One file can contain an infinite number of blocks. Inside each block there at least 3 columns. The left column represents the XX coordinates of the polygon vertices and the right one to the YY coordinates of the polygon vertices. The third column contains the attribute value. A fourth column can be optionally included and it is handled as a character string which can also be used as a legend for each point.

Example

Three columns

<begin_xyz>
-9.138328  38.737320  292. 
<end_xyz>

Four columns

<begin_xyz>
-9.138328  38.737320  292.  MARETEC - IST (Lisbon)
<end_xyz>