Gedaes MATLAB Library

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Gedaes MATLAB Library

• William I. LundgrenGedae, Inc.Telephone 856
  231 4458Fax [phone]Email
  gedae_at_gedae.comWebsite www.gedae.com

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Access to MATLAB through Gedae

• MATLAB code can be executed through a Gedae
  function box
• MATLABs libraries and user-written MATLAB
  routines and applications can be accessed
• Gedae data can be plotted using MATLABs plotting
  routines like plot and mesh
• MATLAB applications can be ported to embeddable
  code piece by piece
• Through Gedaes E-Solaris distributed computing
  capability, MATLAB applications can be
  distributed across workstations

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MATLABs eval Function

• MATLABs eval function allows the user to write a
  string containing MATLAB code and then evaluate
  that string
• gtgt string pi 3
• gtgt eval(string)
• This code creates a variable pi and sets its
  value to 3.
• Gedaes MATLAB library works by allowing the user
  to access this eval function. By setting a
  string parameter Command on the function box, the
  user specifies what MATLAB code to be run by the
  function box

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Eval Function Boxes
Eval function boxes transfer data from the input
stream(s) to MATLAB, then call the eval function
with the supplied Command string, and then
transfer the data back to Gedae
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MATLAB Figures
MATLABs plotting routines can also be accessed,
again using an evaluated string to execute the
MATLAB code. The Hold parameter sets whether the
axis is to be cleared before a new plot is
generated
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MATLAB Terminal

• When developing an application using the Gedae
  MATLAB library, it is useful to have a more
  interactive means of communicating with the
  MATLAB engine
• Without interactive communication, programming,
  and algorithmic errors would be hard to track
  down
• Because other MATLAB boxes are integrated into
  the data flow, onetime commands like labeling a
  figure or printing it would have to be forced
  into Command strings where such commands might
  not naturally fit
• A Gedae GUI, Mlterminal, is provided to allow the
  user to interactively query and communicate with
  the MATLAB engine

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MATLAB Terminal (cont.)
Find values of variables
The Mlterminal is the only way to retrieve text
output from MATLAB function boxes. Enter
commands in the white text entry area and press
Run. The results appear in the pink area below.
Pressing Refresh retrieves text output from other
MATLAB function boxes
MATLABs whos
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Porting MATLAB Applications

• Porting MATLAB applications to embeddable code is
  made easier by using the Gedae MATLAB library.
  Example

Function B mySolve(A,C) Solve C A B where
B and C are n-by-m and A is n-by-n where B is
unknown. A_inv inv(A) B A_inv C
Run this code using the vm_mleval21 function box
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Porting MATLAB Applications (cont.)

• To turn the previous graph into embeddable code,
  divide the algorithm into its two parts. Below
  is a matrix inverse, then a matrix multiply

Then incrementally replace these boxes with
embeddable ones
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Distributed MATLAB

• The MATLAB library can be combined with Gedaes
  E-Solaris capability
• Graphs can be partitioned and mapped to a network
  of workstations such that MATLAB boxes are on
  different processors
• Each E-Solaris processor spawns its own MATLAB
  engine and can execute its own MATLAB code (MIMD)
• Combining MATLAB with E-Solaris allows the user
  to distribute MATLAB applications

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Distributed MATLAB (cont.)
Each family member on a separate processor
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Summary

• All MATLAB routines, including all the products
  libraries and all user-written MATLAB code, can
  be easily incorporated into a Gedae graph
• MATLAB figures can be used to display Gedae data
• MATLAB applications can be more easily ported to
  embeddable Gedae graphs by starting with the
  whole application in one MATLAB box, then
  breaking the application down, and incrementally
  replacing MATLAB boxes with embeddable ones
• Distributed MATLAB applications can be developed
  by combining the MATLAB library with E-Solaris