External Program - Connection to a Program
Every variable type that can be saved and read from a data file has an "External Program" module. Where the program is located depends on the variable type it returns. If the computation returns a collection of variable, use the "External Program" module inside the "Group" variable type.
The first step is to drag the variables that should be used as input into the module.
In this example, the program will use DTSource, the source library. This allows DataTank to help with the coding by creating the project with the IO routines already in place. Later versions of DataTank will allow you to link into a precompiled library - libDT.a instead, but still has the option of containing the source code into the project.
The main routine has been auto-generated to deal with importing the data variables from the input data file and saving the file into the output data file. File access is pretty fast in OS X, and this way debugging becomes much simpler than IO pipes.
The Computation(...) routine is set up to accept the variables already represented with the classes defined in DTSource.