Data item - ObjectVision/GeoDMS GitHub Wiki

The GeoDMS calculates and visualises data. Therefore tree items can to be configured, referring to source data or calculation results. These items are called data items.

From a technical perspective a data item is a reference to a memory array.

StorageManagers are used to read data from files and databases into memory arrays and to write data from these arrays to files.

Small amounts of data, like [parameter]] values or class breaks of [Classifications, are often stored in configuration files.

Configure expressions to calculate with data items.

types

Two types of data items are distinguished:

1. parameter
2. attribute

multi-dimensional

Most data items are one-dimensional. The GeoDMS also supports the following multi-dimensional (spatial) datastructures:

1. point data items: two-dimensional items with for each instance an X and an Y value.
2. sequence of point data item: items with for each instance a non fixed number of coordinates, used for arc and polygon data items.

Different value types and composition types are used to configure multi-dimensional data structures, see units.