The Simulation Studio blocks that can be used to input data to a model are the Numeric Source, Text Source, and Observation Source blocks. In general, three levels of data can be retrieved: a single value, a single row, and an entire data set. The Numeric Source and Text Source blocks provide a stream of single data values by reading a column of data from a SAS data set or JMP table, and the Observation Source block provides a stream of data observation (row) objects from a SAS data set or JMP table. For example, you can use the Observation Source block to read a row of data from a data set and either assign the entire row as entity attributes or assign a subset of the data cell values in the row as attributes. This is demonstrated in the example Using the Observation Source Block to Set Entity Attributes in Appendix E: Examples of Simulation Studio Models. Entity objects in Simulation Studio are tightly integrated with data management schemes, and the Observation Source block provides a straightforward method for creating entities with specific attributes based on input data.
The Observation Source block can also be used to read in an entire SAS data set or JMP table, as shown in the machining example in Figure 12.1. An Observation Source block (labeled Read Dataset) is used to read in the entire machining sequence data set. The data model that represents that data set is passed from the OutData port of the Observation Source block to the InData port of the Dataset Holder block, where it is held until needed.