/* --------------------------------------------------------------------------

Dec. 22, 1990: Beta release date, alt.sources.
Dec. 23, 1990: += and -= operators added to matrix class and nlmdl.opr revised.
Dec. 24, 1990: Used a GNU C++ language extension in realmat.cc to avoid an 
               extra constructor call on returns.  
Dec. 25, 1990: Cleaned up realmat code.
Dec. 26, 1990: Added ++, --, ==, and != operators to matrix class and changed 
               line search in nlmdl.opr.
Dec. 27, 1990: Added <, <=, >, and >= operators to matrix class.
Dec. 28, 1990: Improved efficiency of matrix multiplication in realmat.cc.
Jan.  2, 1991: Fixed bug in nlmdl.cc, s.V initialization loop, should start 
               at "i = 1"  not "i = 0".  Posted notice to alt.sources.
Jan.  4, 1991: Installed at CMU's Statlib mail server.               
Jan.  4, 1991: Improved efficiency of dcond.cc and dsweep.cc.
Jan.  6, 1991: Improved efficiency of matrix transpose in realmat.cc.
Jan.  7, 1991: Eliminated some unnecessary constructor calls in nlmdl.cc
               and nlmdl.opr.
Jan.  7, 1991: Fixed a bug in status.cc.  The address that sscanf reads into 
               should be &y not &x.               
Jan.  8, 1991: Eliminated some unnecessary constructor calls in the examples
               and fixed a bug in ch5eg1/model.cc; data wasn't getting filled
               in correctly when there were missing values.
Jan.  9, 1991: Modified nlmdl.opr to reduce Turbo C++ memory usage; e.g.
               e_t=m.e(t); s.var+=e_t*T(e_t); replaces s.var+=m.e(t)*T(m.e(t)). 
Jan.  9, 1991: Modified status.cc so sscanf reads into a double, not a float.
Jan.  9, 1991: Changed y from float to double in sscanf in status.cc.  That 
               tiny change made status.cc too large for Turbo C++.  Split 
               status.cc into status.cc and display.cc. 
Jan. 10, 1991: Version number 1.0, nlmdl.cc modified to print it.
Jan. 11, 1991: Fixed error in nlmdl.cc; "heterogeneous" should have been 
               "heteroskedastic" in TSLS if test.
Jan. 11, 1991: Version 2.0 release date, comp.sources.misc.
Jan. 12, 1991: Fixed errors in documentation, patch01 posted to ccvr1.
Jan. 20, 1991: Fixed error in dcond.cc documentation.
Oct.  5, 1993: Minor changes to make compatible with HP CC compiler.
Dec. 15, 1993: Minor changes to make compatible with Watcom wcl386 compiler.
Dec. 16, 1993: Changed delete to delete [] in realmat.
Oct.  3, 1994: Minor changes to make compatible with GNU G++ 2.6.0 compiler.
               Dropped support of older GNU compilers and Borland's compiler.
Mar. 19, 2002: Version 2.2.  Updated to Stroustrup 3rd Edition.

------------------------------------------------------------------------- */ 










