1D minimization additions and doc comment

[Jeff Spirko]

I threw together functions for accessing the values of the function
being minimized, which are stored in the minimizer structure.  I
also included a doc string for the functions (check this).  It
seemed cleaner to do it this way than to access the structure
myself.  A patch is attached, referenced to gsl-1.1.1.  Please TEST
the code, I haven't yet. :-(

Also, the use of the terms x_lower, x_upper, and minimum in the docs
caused me to look at the source code to make sure that minimum
wasn't really f_minimum.  Maybe it should be called x_min instead?
Earlier in the Overview section these variables are referred to as
a, b, and x, though I'd prefer the longer names for the code.  Maybe
there should be a sentence relating the two sets of names.

-- 
Jeff Spirko   spirko@lehigh.edu   spirko@yahoo.com   WD3V

The study of non-linear physics is like the study of non-elephant biology.

All theoretical chemistry is really physics;
and all theoretical chemists know it. -- Richard P. Feynman 
-------------- next part --------------
--- ./min/fsolver.c~	Wed Oct  3 06:38:09 2001
+++ ./min/fsolver.c	Tue Apr  2 14:56:27 2002
@@ -173,3 +173,21 @@
   return s->x_upper;
 }
 
+double
+gsl_min_fminimizer_f_minimum (const gsl_min_fminimizer * s)
+{
+  return s->f_minimum;
+}
+
+double
+gsl_min_fminimizer_f_lower (const gsl_min_fminimizer * s)
+{
+  return s->f_lower;
+}
+
+double
+gsl_min_fminimizer_f_upper (const gsl_min_fminimizer * s)
+{
+  return s->f_upper;
+}
+
--- ./min/gsl_min.h~	Sun Jul 15 12:33:06 2001
+++ ./min/gsl_min.h	Tue Apr  2 14:48:03 2002
@@ -77,6 +77,9 @@
 double gsl_min_fminimizer_minimum (const gsl_min_fminimizer * s);
 double gsl_min_fminimizer_x_lower (const gsl_min_fminimizer * s);
 double gsl_min_fminimizer_x_upper (const gsl_min_fminimizer * s);
+double gsl_min_fminimizer_f_minimum (const gsl_min_fminimizer * s);
+double gsl_min_fminimizer_f_lower (const gsl_min_fminimizer * s);
+double gsl_min_fminimizer_f_upper (const gsl_min_fminimizer * s);
 
 int
 gsl_min_test_interval (double x_lower, double x_upper, double epsabs, double epsrel);
--- ./doc/min.texi~	Tue Feb 12 17:34:18 2002
+++ ./doc/min.texi	Tue Apr  2 14:52:29 2002
@@ -233,6 +233,13 @@
 for the minimizer @var{s}.
 @end deftypefun
 
+@deftypefun double gsl_min_fminimizer_f_minimum (const gsl_min_fminimizer *@var{s})
+@deftypefunx double gsl_min_fminimizer_f_upper (const gsl_min_fminimizer *@var{s})
+@deftypefunx double gsl_min_fminimizer_f_lower (const gsl_min_fminimizer *@var{s})
+These functions return the value of the function at the current estimate
+of the minimum and at the upper and lower bounds of interval for the
+minimizer @var{s}.
+
 @node Minimization Stopping Parameters
 @section Stopping Parameters
 @cindex minimization, stopping parameters