Standardising point data sets

This page describes the specification for creating a GISolve2 standard point dataset. The intention of this specification is to standardise point data sets such that each GISolve2 application can read and write point data sets created by other applications without the need for wrapper scripts. Currently, we are unaware of any GIS standardization of point data sets beyond shape files. So we are defining an ASCII based point data standard to use for GISolve2.


File extension: {file}.xyz


In the xyz file there are 3 types of data

xyz values <x value> <y value> <z value> This is the standard data found in point data these are assumed to be FLOAT numbers
reserved key-value pairs #<key> <value> A single pound followed by a reserved key is for machine parsing of defined data
user/machine comment ##<Anything> A user comment is two pounds followed by anything, machines will skip this line


Reserved keywords

npoints Number of points in the file
xllcorner x value of the lower left corner of the bounding box for the points Effectively xmin
yllcorner y value of the lower left corner of the bounding box for the points Effectively ymin
xurcorner x value of the upper right corner of the bounding box for the points Effectively xmax
yurcorner y value of the upper right corner of the bounding box for the points Effectively ymax
NODATA_value Ignore a certain value, or indicate there is no data at this particular point

Valid example

#npoints 3
## Anything can go here, because it is a user comment
## So I will type in stuff .. blah blah blah...
1.2 2.3 34.4
4.3 3.3 43.2
2.3 4.4 53.3