From 7daefc590ab3a810c4ac31d5be5f6ba1b5d3d3d4 Mon Sep 17 00:00:00 2001
From: rnhmjoj <rnhmjoj@inventati.org>
Date: Sat, 7 Mar 2020 01:50:09 +0000
Subject: [PATCH] ex-7: add pre-trained mode

---
 ex-7/main.c | 50 +++++++++++++++++++++++++++++++++++---------------
 makefile    |  2 +-
 2 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/ex-7/main.c b/ex-7/main.c
index 589bd58..7bdd6a0 100644
--- a/ex-7/main.c
+++ b/ex-7/main.c
@@ -9,16 +9,19 @@ struct options {
   size_t nsig;
   size_t nnoise;
   int iter;
+  int trained;
+  double weights[3];
 };
 
 
 int main(int argc, char **argv) {
   /* Set default options */
   struct options opts;
-  opts.mode   = "fisher";
-  opts.nsig   =  800;
-  opts.nnoise = 1000;
-  opts.iter   = 5;
+  opts.mode    = "fisher";
+  opts.nsig    =  800;
+  opts.nnoise  = 1000;
+  opts.iter    = 5;
+  opts.trained = 0;
 
   /* Process CLI arguments */
   for (size_t i = 1; i < argc; i++) {
@@ -26,13 +29,20 @@ int main(int argc, char **argv) {
     else if (!strcmp(argv[i], "-s")) opts.nsig = atol(argv[++i]);
     else if (!strcmp(argv[i], "-n")) opts.nnoise = atol(argv[++i]);
     else if (!strcmp(argv[i], "-i")) opts.nnoise = atoi(argv[++i]);
+    else if (!strcmp(argv[i], "-w")) {
+      opts.trained = 1;
+      for (int j = 0; j < 3; j++)
+        opts.weights[j] = atof(argv[++i]);
+    }
     else {
-      fprintf(stderr, "Usage: %s -[hiIntp]\n", argv[0]);
-      fprintf(stderr, "\t-h\tShow this message.\n");
-      fprintf(stderr, "\t-m MODE\tThe disciminant to use: 'fisher' for "
+      fprintf(stderr, "Usage: %s -[hminw]\n", argv[0]);
+      fprintf(stderr, "  -h\t\tShow this message.\n");
+      fprintf(stderr, "  -m MODE\tThe training mode to use: 'fisher' for \n\t\t"
                       "Fisher linear discriminant, 'percep' for perceptron.\n");
-      fprintf(stderr, "\t-i N\tThe number of training iterations (for perceptron).\n");
-      fprintf(stderr, "\t-n N\tThe number of events in noise class.\n");
+      fprintf(stderr, "  -i N\t\tThe number of training iterations "
+                       "(for perceptron only).\n");
+      fprintf(stderr, "  -n N\t\tThe number of events in noise class.\n");
+      fprintf(stderr, "  -w W₁ W₂ B\tSet weights and bias (if pre-trained).\n");
       return EXIT_FAILURE;
     }
   }
@@ -52,9 +62,19 @@ int main(int argc, char **argv) {
   sample_t *noise  = generate_normal(r, opts.nnoise, &par_noise);
 
   gsl_vector *w;
-  double t_cut;
+  double cut;
 
-  if (!strcmp(opts.mode, "fisher")) {
+  if (opts.trained) {
+    /* Pre-trained
+     *
+     * Use the provided weigths and bias.
+     */
+    fputs("# Pre-trained \n\n", stderr);
+    gsl_vector_view v = gsl_vector_view_array(opts.weights, 2);
+    w = &v.vector;
+    cut = opts.weights[2];
+  }
+  else if (!strcmp(opts.mode, "fisher")) {
     /* Fisher linear discriminant
      *
      * First calculate the direction w onto
@@ -65,7 +85,7 @@ int main(int argc, char **argv) {
     fputs("# Linear Fisher discriminant\n\n", stderr);
     double ratio = opts.nsig / (double)opts.nnoise;
     w = fisher_proj(signal, noise);
-    t_cut = fisher_cut(ratio, w, signal, noise);
+    cut = fisher_cut(ratio, w, signal, noise);
   }
   else if (!strcmp(opts.mode, "percep")) {
     /* Perceptron
@@ -75,7 +95,7 @@ int main(int argc, char **argv) {
      * solution in `iter` iterations.
      */
     fputs("# Perceptron \n\n", stderr);
-    w = percep_train(signal, noise, opts.iter, &t_cut);
+    w = percep_train(signal, noise, opts.iter, &cut);
   }
   else {
     fputs("\n\nerror: invalid mode. select either"
@@ -89,9 +109,9 @@ int main(int argc, char **argv) {
   fprintf(stderr, "* w: [%.3f, %.3f]\n",
       gsl_vector_get(w, 0),
       gsl_vector_get(w, 1));
-  fprintf(stderr, "* t_cut: %.3f\n", t_cut);
+  fprintf(stderr, "* cut: %.3f\n", cut);
   gsl_vector_fprintf(stdout, w, "%g");
-  printf("%f\n", t_cut);
+  printf("%f\n", cut);
 
   /* Print data to stdout for plotting.
    * Note: we print the sizes to be able
diff --git a/makefile b/makefile
index 03de3f9..c0e3626 100644
--- a/makefile
+++ b/makefile
@@ -24,7 +24,7 @@ ex-5/bin/%: ex-5/%.c
 ex-6/bin/main: ex-6/rl.c ex-6/fft.c
 	$(CCOMPILE)
 
-ex-7/bin/main: ex-7/main.c ex-7/common.c ex-7/fisher.c
+ex-7/bin/main: ex-7/main.c ex-7/common.c ex-7/fisher.c ex-7/percep.c
 	$(CCOMPILE)
 
 misc/pdfs: misc/pdfs.c