From cca0b71032a6c55d5c525421b1daa8be72087640 Mon Sep 17 00:00:00 2001
From: Gustav Louw <yellingintothefan@gmail.com>
Date: Fri, 30 Mar 2018 15:42:20 -0700
Subject: [PATCH] saving and loading functions

---
 Tinn.c | 36 +++++++++++++++++++++++++++++++++---
 Tinn.h | 20 ++++++++++++++++++--
 test.c | 18 ++++++++++++------
 3 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/Tinn.c b/Tinn.c
index fe0e9de..2066b8b 100644
--- a/Tinn.c
+++ b/Tinn.c
@@ -1,5 +1,6 @@
 #include "Tinn.h"
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <math.h>
 #include <time.h>
@@ -90,8 +91,7 @@ static void forewards(const Tinn t, const double* in)
 // Randomizes weights and biases.
 static void twrand(const Tinn t)
 {
-    int wgts = t.nhid * (t.nips + t.nops);
-    for(int i = 0; i < wgts; i++) t.w[i] = frand() - 0.5;
+    for(int i = 0; i < t.nw; i++) t.w[i] = frand() - 0.5;
     for(int i = 0; i < t.nb; i++) t.b[i] = frand() - 0.5;
 }
 
@@ -113,7 +113,8 @@ Tinn xtbuild(int nips, int nhid, int nops)
     Tinn t;
     // Tinn only supports one hidden layer so there are two biases.
     t.nb = 2;
-    t.w = (double*) calloc(nhid * (nips + nops), sizeof(*t.w));
+    t.nw = nhid * (nips + nops);
+    t.w = (double*) calloc(t.nw, sizeof(*t.w));
     t.b = (double*) calloc(t.nb, sizeof(*t.b));
     t.h = (double*) calloc(nhid, sizeof(*t.h));
     t.o = (double*) calloc(nops, sizeof(*t.o));
@@ -125,9 +126,38 @@ Tinn xtbuild(int nips, int nhid, int nops)
     return t;
 }
 
+void xtsave(const Tinn t, const char* path)
+{
+    FILE* file = fopen(path, "w");
+    // Header.
+    fprintf(file, "%d %d %d\n", t.nips, t.nhid, t.nops);
+    // Biases and weights.
+    for(int i = 0; i < t.nb; i++) fprintf(file, "%lf\n", t.b[i]);
+    for(int i = 0; i < t.nw; i++) fprintf(file, "%lf\n", t.w[i]);
+    fclose(file);
+}
+
+Tinn xtload(const char* path)
+{
+    FILE* file = fopen(path, "r");
+    int nips = 0;
+    int nhid = 0;
+    int nops = 0;
+    // Header.
+    fscanf(file, "%d %d %d\n", &nips, &nhid, &nops);
+    // A new tinn is returned.
+    Tinn t = xtbuild(nips, nhid, nips);
+    // Biases and weights.
+    for(int i = 0; i < t.nb; i++) fscanf(file, "%lf\n", &t.b[i]);
+    for(int i = 0; i < t.nw; i++) fscanf(file, "%lf\n", &t.w[i]);
+    fclose(file);
+    return t;
+}
+
 void xtfree(const Tinn t)
 {
     free(t.w);
+    free(t.b);
     free(t.h);
     free(t.o);
 }
diff --git a/Tinn.h b/Tinn.h
index baec2f6..10e504a 100644
--- a/Tinn.h
+++ b/Tinn.h
@@ -10,16 +10,32 @@ typedef struct
     // Number of biases - always two - Tinn only supports a single hidden layer.
     int nb;
 
+    // Number of weights.
+    int nw;
+
     int nips; // Number of inputs.
     int nhid; // Number of hidden neurons.
     int nops; // Number of outputs.
 }
 Tinn;
 
+// Trains a tinn with an input and target output with a learning rate.
+// Returns error rate of the neural network.
 double xttrain(const Tinn, const double* in, const double* tg, double rate);
 
+// Builds a new tinn object given number of inputs (nips),
+// number of hidden neurons for the hidden layer (nhid),
+// and number of outputs (nops).
 Tinn xtbuild(int nips, int nhid, int nops);
 
-void xtfree(Tinn);
-
+// Returns an output prediction given an input.
 double* xpredict(const Tinn, const double* in);
+
+// Saves the tinn to disk.
+void xtsave(const Tinn, const char* path);
+
+// Loads a new tinn from disk.
+Tinn xtload(const char* path);
+
+// Frees a tinn from the heap.
+void xtfree(const Tinn);
diff --git a/test.c b/test.c
index 3423374..7141839 100644
--- a/test.c
+++ b/test.c
@@ -133,12 +133,12 @@ int main()
     // Hyper Parameters.
     // Learning rate is annealed and thus not constant.
     const int nhid = 32;
-    double rate = 0.5;
+    double rate = 1.0;
     // Load the training set.
     const Data data = build("semeion.data", nips, nops);
-    // Rock and roll.
+    // Train, baby, train.
     const Tinn tinn = xtbuild(nips, nhid, nops);
-    for(int i = 0; i < 100; i++)
+    for(int i = 0; i < 30; i++)
     {
         shuffle(data);
         double error = 0.0;
@@ -149,16 +149,22 @@ int main()
             error += xttrain(tinn, in, tg, rate);
         }
         printf("error %.12f :: rate %f\n", error / data.rows, rate);
-        rate *= 0.99;
+        rate *= 0.9;
     }
+    // This is how you save the neural network to disk.
+    xtsave(tinn, "saved.tinn");
+    xtfree(tinn);
+    // This is how you load the neural network from disk.
+    const Tinn loaded = xtload("saved.tinn");
     // Ideally, you would load a testing set for predictions,
     // but for the sake of brevity the training set is reused.
     const double* const in = data.in[0];
     const double* const tg = data.tg[0];
-    const double* const pd = xpredict(tinn, in);
+    const double* const pd = xpredict(loaded, in);
     for(int i = 0; i < data.nops; i++) { printf("%f ", tg[i]); } printf("\n");
     for(int i = 0; i < data.nops; i++) { printf("%f ", pd[i]); } printf("\n");
-    xtfree(tinn);
+    // Cleanup.
+    xtfree(loaded);
     dfree(data);
     return 0;
 }