curveopt: try simple, but no good

[moebius3.git] / findcurve.c

diff --git a/findcurve.c b/findcurve.c
index 65c5672eb7753c5a117d741c2723fda43c2f7a5b..ca3cd8fd4ae76c2ab12ddcd5cdccc7b4e0d1cb6a 100644 (file)
--- a/findcurve.c
+++ b/findcurve.c
@@ -2,11 +2,14 @@
  */
 
 #include <math.h>
+#include <string.h>
+#include <assert.h>
 
 #include <gsl/gsl_errno.h>
 #include <gsl/gsl_sf.h>
 #include <gsl/gsl_siman.h>
 #include <gsl/gsl_randist.h>
+#include <gsl/gsl_multimin.h>
 
 #include "symbolic.c"
 
@@ -21,67 +24,85 @@ static inline double sinc(double x) {
   return gsl_sf_sinc(x / M_PI);
 }
 
+static int NP;
 static double *INPUT; /* dyanmic array, on main's stack */
 static double PREP[NPREP];
 
+#define GET_X(xg)                                      \
+  double X[NX];                                                \
+  ({ int get_x_i;                                      \
+     for (get_x_i=0; get_x_i<NX; get_x_i++)            \
+       X[get_x_i] = gsl_vector_get(xg, get_x_i);       \
+  })
+
+static void printcore(const double *X) {
+  int i, j;
+  DECLARE_F_G;
+  CALCULATE_F_G;
+  printf("[");
+  for (i=0; i<NP; i++)
+    for (j=0; j<3; j++)
+      printf(" %25.18g,", POINT(i)[j]);
+  printf(" ]\n");
+}
+
 static void prepare(double X[] /* startpoint */) {
   /* fills in PREP and startpoint */
   PREPARE;
 }
 
-static double cb_Efunc(void *xp) {
-  const double *X = xp;
-  double F[3], G[3];
+//#define DEBUG
 
+static double cb_f(const gsl_vector *xg, void *params) {
+  int P;
+
+  GET_X(xg);
+
+  DECLARE_F_G;
   CALCULATE_F_G;
 
-  double e = 0;
-  for (P=0; P<NP-3; P++) {
-    double P_cost;
-    CALCULATE_COST;
-    e += P_cost;
+#ifdef DEBUG
+  int i,j;
+  printf(" Efunc\n");
+  for (j=0; j<3; j++) {
+    for (P=0; P<NP; P++)
+      printf(" %7.4f", POINT(P)[j]);
+    printf("\n");
   }
-  return e;
+  printf("             ");
+#endif
+
+  CALCULATE_COST;
+  return cost;
 }
 
-static void cb_step(const gsl_rng *rng, void *xp, double step_size) {
+static void __attribute__((unused))  cb_step(const gsl_rng *rng, void *xp, double step_size) {
   double *x = xp;
   int i;
   double step[NX];
-  gsl_ran_dir_nd(rng, N,step);
-  for (i=0; i<N; i++)
+  gsl_ran_dir_nd(rng, NX, step);
+  for (i=0; i<NX; i++)
     x[i] += step_size * step[i];
   //printf("\n cb_step %p %10.7f [", xp, step_size);
   //for (i=0; i<N; i++) printf(" %10.7f,", step[i]);
   //printf("]\n");
 }
 
-static double cb_metric(void *xp, void *yp) {
+static double __attribute__((unused))  cb_metric(void *xp, void *yp) {
   const double *x=xp, *y=yp;
   int i;
   double s;
-  for (i=0, s=0; i<N; i++) {
+  for (i=0, s=0; i<NX; i++) {
     double d = x[i] - y[i];
     s += d*d;
   }
   return sqrt(s);
 }
 
-static void printcore(const double *x) {
-  int i;
-  double F[N];
-  X_EXTRACT;
-  F_POPULATE;
-  printf("[");
-  for (i=0; i<6; i++) printf(" %.18g,", x[i]);
-  for (i=0; i<6; i++) printf(" %.18g,", F[i]);
-  printf(" ]\n");
-}
-
-static void __attribute__((unused)) cb_print(void *xp) {
-  const double *x = xp;
+static void __attribute__((unused)) cb_print(gsl_vector *xp) {
+  GET_X(xp);
   printf("\n");
-  printcore(x);
+  printcore(X);
 }
 
 static double scan1double(void) {
@@ -95,44 +116,54 @@ static double scan1double(void) {
   return v;
 }
 
-int main(int argc, const char *const argv) {
+int main(int argc, const char *const *argv) {
   double epsilon;
-  int i;
+  int i, r;
 
   NP = atoi(argv[1]);
+  epsilon = atof(argv[2]);
 
-  gsl_rng *rng = gsl_rng_alloc(gsl_rng_ranlxd2);
-
+  double startpoint_X[NX];
   double input[NINPUT]; INPUT = input;
-  double startpoint[NX];
+
+  gsl_multimin_function func = {
+    .f = cb_f,
+    .n = NX,
+    .params = 0,
+  };
+
+  gsl_vector *current_gx = gsl_vector_alloc(NX);
+  gsl_vector *step_size = gsl_vector_alloc(NX);
+  gsl_vector_set_all(step_size, 0.01);
+
+  gsl_multimin_fminimizer *minimiser =
+    gsl_multimin_fminimizer_alloc(gsl_multimin_fminimizer_nmsimplex2rand, NX);
 
   for (;;) {
     /* NINPUT + 1 doubles: startpoint, epsilon for residual */
     for (i=0; i<NINPUT; i++)
       INPUT[i] = scan1double();
-    epsilon = scan1double();
 
-    gsl_rng_set(rng,0);
+    prepare(startpoint_X);
+    for (i=0; i<NX; i++)
+      gsl_vector_set(current_gx, i, startpoint_X[i]);
+
+    r = gsl_multimin_fminimizer_set(minimiser, &func, current_gx, step_size);
+    assert(!r);
+
+    for (;;) {
+      r = gsl_multimin_fminimizer_iterate(minimiser);
+      assert(!r);
 
-    gsl_siman_params_t siman_params = {
-      .k = 1.0,
-      .t_initial = 0.5,
-      .mu_t = 1.001,
-      .t_min = epsilon * 1E-3,
-      .iters_fixed_T = 100,
-      .n_tries = 10,
-      .step_size = 0.05,
-    };
+      //cb_print(current_gx);
 
-    prepare(startpoint);
+      double size = gsl_multimin_fminimizer_size(minimiser);
+      //printf(" size=%10.7f\n", size);
 
-    gsl_siman_solve(rng,
-                   startpoint,
-                   cb_Efunc, cb_step, cb_metric,
-                   0, // cb_print,
-                   0,0,0, sizeof(startpoint), siman_params);
+      if (size < epsilon) break;
+    }      
 
-    printcore(startpoint);
+    cb_print(current_gx);
 
     printf("[]\n");
     fflush(stdout);