CIFER®-MATLAB Interfaces: Development and ... - Cal Poly

CIFER ® inputs from the old interface, which was split up over a long series of screens, provided
significant challenge. The command line function had to emulate all of that error checking
structure at one time. Appendix A contains example screen shots of all the screens for the
COMPOSITE program within CIFER ® . Each screen is navigated through using the keyboard, and
error checking occurs when the user progresses from one screen to another.
3.1.1 Development Process
The first step in the development process was to determine the best method to get information
from the CIFER ® database into the MATLAB workspace. The solution lay in MATLAB’s ability
to create “mex” functions that can interface with Fortran or C code. CIFER ® ’s original Fortran
code is structured such that it has internal functions and subroutines to access important
information. By making the appropriate calls in the mex code, these functions were successful in
passing data from the CIFER ® Fortran into the MATLAB workspace and vice versa. The mex
functions became the building blocks of all the CIFER ® -MATLAB interface code.
The concept of using internal CIFER ® functions with mex code was initially tested with some
very basic functions designed purely to retrieve a few specific pieces of data from CIFER ® , such
as a frequency response name and description, and display them in MATLAB. Modifications
were made to the data in MATLAB and fed back into CIFER ® . Accessing the frequency response
in CIFER ® verified whether or not the change was successful.
When data is first processed in CIFER ® it becomes known as a ‘case.’ which encompasses a
series of measurements from a system. For example, one of the sample cases included with
CIFER ® is called XVLATSWP, which is for lateral responses from the XV-15 research vehicle in
hover. The case structure has all the information that dictates where data is located, how to
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