added ANSI C variant

bin/NLMS_ANSI_C.c

@@ -0,0 +1,225 @@
+//
+//  main.c
+//  NLMS
+//
+//  Created by Stefan Fiese on 26.04.18.
+//  Copyright © 2018 Stefan Fiese. All rights reserved.
+//
+
+#include <stdio.h>
+#include <math.h>
+#include <time.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define M 1000
+#define tracking 40; //Count of weights
+//static Stack<double> x = new Stack<double>();
+//static Random rnd = new Random();
+//static double[] _x = new double[M];
+//static double[,] w = new double[M, M];
+#define learnrate 1.0
+
+double x[] ={0};
+double _x[M] = {0};
+double w [M][M]={{0},{0}};
+
+char filename(void);
+double sum_array(double x[], int length);
+void direkterVorgaenger(void);
+void lokalerMittelWert(void);
+
+double r2()
+{
+    return((rand() % 10000) / 10000.0);
+}
+
+int rnd()
+{
+    double u;
+    u = r2();
+    return u;
+}
+
+
+
+
+int main(int argc, char **argv ) {
+
+    int i = 0;
+    for (i = 0; i < M; i++) {
+        _x[i] += ((255.0 / M) * i);
+        for (int k = 1; k < M; k++)
+        {
+            w[k][i] = rnd();
+            //Console.WriteLine(String.Format("Weight: {0}", w[k, i]));
+        }
+        
+    }
+    
+    for (i = 0; i < tracking; i++){
+        for (int k = 1; k < tracking; k++)
+        {
+            const char *name = fileName();
+            FILE *fp = fopen(*name,"wb+");
+            File.AppendAllText("weights.txt",
+                               String.Format("[{0}][{1}] {2}\n", k, i, Math.Round(w[k, i], 2).ToString()),
+                               Encoding.UTF8);
+        }
+    }
+    
+    direkterVorgaenger();
+    
+    for (i = 0; i < tracking; i++) {
+        for (int k = 1; k < tracking; k++) {
+            File.AppendAllText("weights_after.txt",
+                               String.Format("[{0}][{1}] {2}\n", k, i, Math.Round(w[k, i], 2).ToString()),
+                               Encoding.UTF8);
+        }
+        
+    }
+    
+    
+    getchar();
+    
+}
+
+void lokalerMittelWert()
+{
+    int i;
+    for (i=1; i < M; i++){
+   // while (x.Count + 1 < M)
+        double x_pred = 0.0;
+        double x_middle = (i > 0) ? sum_array(x,i) / i : 0;
+        double x_actual = _x[i];
+        
+        for (int j = 1; j < i; j++)
+        {
+            x_pred += (w[j, i] * (x[i - j] - x_middle));
+        }
+        x_pred += x_middle;
+        
+        //Console.WriteLine(String.Format("X_sum: {0}", x_middle));
+        
+       printf("X_pred: {%f}", x_pred);
+       printf("X_actual: {%f}", x_actual);
+        
+        double x_error = x_actual - x_pred;
+        double x_square = 0;
+        
+        for (int k = 1; k <= i; k++)
+        {
+            x_square += pow(x[i - k], 2);
+        }
+        
+        for (int l = 1; l < i; l++)
+        {
+            w[l, i + 1] = w[l, i] + learnrate * x_error * (x[i - l] / x_square);
+        }
+    }
+}
+
+static void direkterVorgaenger()
+{
+    double x_error[M] = {0};
+    int i;
+    for(i = 0; i < M; i++)
+    //while (x.Count + 1 < M)
+    {
+        double x_pred = 0.0;
+        //double[] x_array = _x;
+        double x_actual = _x[i + 1];
+        if (x.Count > 0)
+        {
+            for (int j = 1; j < i; j++)
+            {
+                x_pred += (w[j, i] * (_x[i - j] - _x[i - j - 1]));
+            }
+            x_pred += x[i - 1];
+            
+            //Console.WriteLine(String.Format("X_sum: {0}", x_middle));
+            
+            //Console.WriteLine(String.Format("X_pred: {0}", x_pred));
+            File.AppendAllText("direkterVorgaenger.txt",
+                               String.Format("{0}. X_pred {1}\n",x.Count, x_pred),
+                               Encoding.UTF8);
+            //Console.WriteLine(String.Format("X_actual: {0}", x_actual));
+            File.AppendAllText("direkterVorgaenger.txt",
+                               String.Format("{0}. X_actual {1}\n", x.Count, x_actual),
+                               Encoding.UTF8);
+            
+            x_error[x.Count] = x_actual - x_pred;
+            
+            //Console.WriteLine(String.Format("X_error: {0}", x_error));
+            File.AppendAllText("direkterVorgaenger.txt",
+                               String.Format("{0}. X_error {1}\n\n", x.Count, x_error),
+                               Encoding.UTF8);
+            double x_square = 0;
+            
+            for (int k = 1; k < i; k++)
+            {
+                x_square += pow(_x[i - k] - _x[i - k - 1], 2);
+            }
+            //Console.WriteLine(String.Format("X_square: {0}", x_square));
+            //File.AppendAllText("direkterVorgaenger.txt",
+            //    String.Format("{0}. X_square {1}\n", x.Count, x_square),
+            //    Encoding.UTF8);
+            //File.AppendAllText("x_array.txt",
+            //    String.Format("{0}. X_array {1}\n", x.Count, x_array[x.Count - 1]),
+            //    Encoding.UTF8);
+            for (int l = 1; l < i; l++)
+            {
+                w[l, i + 1] = w[l, i] + learnrate * x_error[i] * ((_x[i - l] - x_array[i - l - 1]) / x_square);
+            }
+        }
+    }
+    int x_error_array_length = sizeof(error_array_length)/sizeof(error_array_length[0])
+    double mittel = sum_array(x_error, x_error_array_length) / x_error_array_length;
+    double varianz = 0.0;
+    for (i = 0; i <= x_error_array_length; i++)
+    //foreach(double x_e in x_error)
+    {
+        varianz += pow(x_e - mittel, 2);
+    }
+    varianz /= x_error_array_length;
+    File.AppendAllText("ergebnisse.txt",
+                       String.Format("Quadratische Varianz(x_error): {0}\n Mittelwert(x_error): {1}\n\n", varianz, mittel),
+                       Encoding.UTF8);
+}
+
+
+char fileName(char *fname){
+    //filename
+    char date[34];
+    //char name[13] = "_results.txt";
+    time_t now;
+    now = time(NULL);
+    strftime(date, 20, "%Y-%m-%d_%H_%M_%S", localtime(&now));
+    strcpy(date,*fname);
+    //return &date[0];
+    return date;
+}
+
+/*
+ 
+ ===================================
+ 
+ sum_array
+ 
+ 
+ sum of all elements in x
+ within a defined length
+ 
+ ====================================
+ 
+ */
+
+double sum_array(double x[], int length){
+    //int length = 0;
+    double sum = 0.0;
+    //length = sizeof(x)/sizeof(x[0]);
+    for (i=0; i< length; i++){
+        sum += x[i];
+    }
+    return sum;
+}