The Block Attribute Table

In the previous Quick Tour chapter we took a look at the block attribute table, and noted that the rows corresponded to polygons in the dataset, that columns correspond to attributes, and that the table had a time dimension that could be used to view results by planning period. The organization of the block attribute is important, s we will mention it again here briefly. Other sections will describe the contents of this table in greater detail (see the section called “The Block Attribute Table” and the section called “The Block Attribute Table”).

Although some attributes in the block table are 'static' and remain constant across all planning periods, others are 'dynamic', and vary with the age of the stand (or time since treatment). Dynamic attributes are age dependent, and can be viewed as presenting a virtual cube of data. In this cube, each row is a block, each column is an attribute and each rank of the Z-axis is a period (see Figure 22, “Cube of data - Blocks, attributes and planning horizons ”).

As we saw in the Quick Tour, the Patchworks table viewer displays the records and attributes in two dimensions. For tables which include dynamic attributes which change over time, the third dimension of time is represented by a scroll bar on the right hand side of the window displaying all the periods in the planning horizon. Attribute tables provide opportunities to examine detailed record data at any time period. They also provides tools to query, sort and summarize information.

Figure 22. Cube of data - Blocks, attributes and planning horizons

The dynamic attributes in the block table present a virtual cube of data represented by rows (records), columns (attributes) and a Z-axis (periods).