Modified to conform to the More-Thuente paper. Simplified interpolation to

use secant rather than polynomial fits. Simplified activation of debug printout.


git-svn-id: http://qboxcode.org/svn/qb/trunk@1013 cba15fb0-1239-40c8-b417-11db7ca47a34

src/LineMinimizer.h

@@ -25,28 +25,35 @@ class LineMinimizer
 
   double f0,fp0,fm,fpm,f_low,fp_low,f_high,fp_high,
          alpha_m,alpha_low,alpha_high;
-  bool first_use, done_, fail_, bracketing;
-  double alpha_start_, sigma1_, sigma2_;
+  bool first_use, done_, fail_, bracketing, use_psi;
+  bool debug_print;
+  double alpha_start_, alpha_max_, sigma1_, sigma2_;
   int nstep_, nstep_max_;
 
+  double psi(double alpha, double f) { return f - f0 - alpha * fp0 * sigma1_; }
+  double psip(double fp) { return fp - fp0 * sigma1_; }
   double interpolate(void);
 
   public:
 
-  LineMinimizer(void) : sigma1_(0.1), sigma2_(0.5), alpha_start_(1.0),
-   first_use(true), done_(false), fail_(false), bracketing(false), nstep_(0),
-   nstep_max_(10) {}
+  LineMinimizer(void) : sigma1_(0.1), sigma2_(0.5), alpha_start_(0.1),
+   alpha_max_(1.0), first_use(true), done_(false), fail_(false),
+   bracketing(false), use_psi(true), nstep_(0), nstep_max_(5), 
+   debug_print(false) {}
   void reset(void) { first_use = true; done_ = false; fail_ = false;
     bracketing = false; nstep_ = 0; }
   double sigma1(void) const { return sigma1_; }
   double sigma2(void) const { return sigma2_; }
   double alpha_start(void) const { return alpha_start_; }
+  double alpha_max(void) const { return alpha_max_; }
   bool done(void) const { return done_; }
   bool fail(void) const { return fail_; }
 
   void set_sigma1(double s) { sigma1_ = s; }
   void set_sigma2(double s) { sigma2_ = s; }
   void set_alpha_start(double a) { alpha_start_ = a; }
+  void set_alpha_max(double a) { alpha_max_ = a; }
+  void set_debug_print(void) { debug_print = true; }
 
   double next_alpha(double alpha, double f, double fp);
 };