GRADSIM Simulator Update

[Raymond Watrous]

Subject: GRADSIM Connectionist Network Simulator Version 1.7

Corrections: A bug in the line_search module was discovered and repaired;
	the bug could result in a line search which was not closed.

Enhancements: The line_search algorithm was enhanced to conform to the one
	described in R. Fletcher, Practical Optimization (2nd edition) 1987.
	The absolute value of the slope is now used in the termination test;
	this results in termination being more carefully controlled by
	the slope criterion parameter.

Testing: The line_search bug was confirmed in a test of the BFGS algorithm
	on the Rosenbrock function from 100 random starting points. The bug
	was evident in 18 cases. The correction of the bug was confirmed for
	these same 100 starting points. The enhanced algorithm was also tested
	and required slightly fewer iterations then the corrected algorithm.

Checking: Two test results are now included in the archive for checking the
	simulator.

	1. The results of the BFGS algorithm on the Rosenbrock function
	from the start point (-1.2, 1.0) are listed. This checks the
	bfgs and line_search modules.

	2. The results several iterations of the BFGS algorithm on a simple
	speech example. This checks the speech I/O, function and gradient
	evaluation modules.

	Make files are included in the archive for generating the simulator
	for these checks.

Documentation:

	The GRADSIM simulator is briefly described in the University of
	Pensylvania Tech Report MS-CIS-88-16.

		GRADSIM: A connectionist network simulator
		using gradient optimization techniques.

	An excerpt of the relevant part of this report is now included in the
	gradsim archive.

Access:
	The GRADSIM simulator may be obtained in compressed tar format via
	anonymous ftp from linc.cis.upenn.edu as /pub/gradsim.tar.Z.

	The simulator may also be obtained in uuencoded tar format
	by email from carol at ai.toronto.edu.