Subprocess

Synopsis

This operator introduces a process within a process. Whenever a Subprocess operator is reached during a process execution, first the entire subprocess is executed. Once the subprocess execution is complete, the flow is returned to the process (the parent process). A subprocess can be considered as a small unit of a process, like in process, all operators and combination of operators can be applied in a subprocess. That is why a subprocess can also be defined as a chain of operators that is subsequently applied.

Description

Double click on the Subprocess operator to go inside the subprocess. The subprocess is then shown in the same Process View. To go back to the parent process, click the blue-colored up arrow button in the Process View toolbar. This works like files and folders work in operating systems. Subprocesses can have subprocesses in them just like folders can have folders in them. The order of execution in case of nested subprocesses is the same as a depth-first-search through a tree structure. When a Subprocess operator is reached, all operators inside it are executed and then the execution flow returns to the parent process and the operator that is located after the Subprocess operator (in the parent process) is executed. This description can be easily understood by studying the attached Example Process.

A subprocess can be considered as a simple operator chain which can have an arbitrary number of inner operators. The operators are subsequently applied and their output is used as input for the succeeding operators. The input of the Subprocess operator is used as input for the first operator in it and the output of the last operator in the subprocess is used as the output of the Subprocess operator. Subprocesses make a process more manageable but don't forget to connect all inputs and outputs in correct order. Also make sure that you have connected the right number of ports at all levels of the chain.

Subprocesses are useful in many ways. They give a structure to the entire process. Process complexity is reduced and they become easy to understand and modify. Many operators have a subprocess as their integral parts e.g. the X-Validation operator which is also shown in the attached Example Process. It should be noted that connecting the input of a Subprocess directly to its output without applying any operator in between or using an empty Subprocess gives no results.

Input

input

The Subprocess operator can have multiple inputs. When one input is connected, anotherinputport becomes available which is ready to accept another input (if any). The order of inputs remains the same. The Object supplied at the firstinputport of the subprocess is available at the firstinputport of the nested chain (inside the subprocess). Subprocesses make a process more manageable but don't forget to connect all inputs in correct order. Make sure that you have connected the right number of ports at all levels of the chain.

Output

output

The Subprocess operator can have multiple outputs. When one output is connected, anotheroutputport becomes available which is ready to deliver another output (if any). The order of outputs remains the same. The Object delivered at the firstoutputport of the subprocess is delivered at the firstoutputof the outer process. Subprocesses make a process more manageable but don't forget to connect all outputs in correct order. Make sure that you have connected the right number of ports at all levels of the chain.