8 files changed, 151 insertions, 3 deletions

diff --git a/Makefile b/Makefile
index 0eafcb5..817c0e2 100644
--- a/Makefile
+++ b/Makefile
@@ -2,8 +2,10 @@
 Q1: Q1.cpp mysqrt.cpp mysqrt.h
 	g++ -o Q1 mysqrt.cpp Q1.cpp
 
+Q2: Q2.cpp write_data.cpp statistics.h get_mean.cpp get_mode.cpp get_maximum.cpp get_minimum.cpp
+	g++ -o Q2 write_data.cpp get_mean.cpp get_mode.cpp get_maximum.cpp get_minimum.cpp Q2.cpp
+
 Q3a: Q3a.cpp
 	g++ -o Q3a Q3a.cpp
 
 Q3b: Q3b.cpp
-	g++ -o Q3b Q3b.cpp
diff --git a/Q2.cpp b/Q2.cpp
index e69de29..30fd0a9 100644
--- a/Q2.cpp
+++ b/Q2.cpp
@@ -0,0 +1,32 @@
+
+#include <iostream>
+
+#include "statistics.h"
+
+using namespace std;
+
+int main(int argc, const char *argv[])
+{
+    char input[256]; // max filename length for most systems
+
+    float mean, min, max, mode;
+
+    cout << "Please input a filename to use for data" << endl;
+    cout << ">> ";
+    cin >> input;
+
+    if (argc > 1)
+        write_data(input, 1000, 500);
+
+    mean = get_mean(input);
+    min = get_minimum(input);
+    max = get_maximum(input);
+    mode = get_mode(input);
+    
+    cout << "Mean: " << mean << endl;
+    cout << "Min: " << min << endl;
+    cout << "Max: " << max << endl;
+    cout << "Mode: " << mode << endl;
+
+    return 0;
+}
diff --git a/get_maximum.cpp b/get_maximum.cpp
index e69de29..c98d897 100644
--- a/get_maximum.cpp
+++ b/get_maximum.cpp
@@ -0,0 +1,36 @@
+
+#include "statistics.h"
+
+using namespace std;
+float get_maximum(const char *filename)
+{
+    ifstream in;
+    in.open(filename);
+
+    unsigned size = 1024;
+    int *data = new int[size];
+
+    int i = 0;
+
+    while (!in.eof()) {
+        in >> data[i];
+        i++;
+        
+        if (i >= size) { // reallocate. Where is realloc in C++?
+            size *= 2;
+            int *newdata = new int[size];
+            for (int j = 0; j <= i; j++)
+                newdata[j] = data[j];
+            delete data;
+            data = newdata;
+        }
+    }
+
+    i--;
+    int max = data[0];
+    for (int j = 0; j < i; j++)
+        if (data[j] > max)
+            max = data[j];
+
+    return max;
+}
diff --git a/get_mean.cpp b/get_mean.cpp
index e69de29..f62f606 100644
--- a/get_mean.cpp
+++ b/get_mean.cpp
@@ -0,0 +1,25 @@
+
+#include "statistics.h"
+
+using namespace std;
+
+float get_mean(const char *filename)
+{
+    ifstream in;
+    in.open(filename);
+
+    int count = 0;
+    float sum = 0;
+
+    int cur = 0;
+
+    while (!in.eof()) {
+        in >> cur;
+        sum += cur;
+        count++;
+    }
+
+    in.close();
+
+    return sum/count;
+}
diff --git a/get_minimum.cpp b/get_minimum.cpp
index e69de29..e994c98 100644
--- a/get_minimum.cpp
+++ b/get_minimum.cpp
@@ -0,0 +1,34 @@
+#include "statistics.h"
+
+using namespace std;
+float get_minimum(const char *filename)
+{
+    ifstream in;
+    in.open(filename);
+
+    unsigned size = 1024;
+    int *data = new int[size];
+
+    int i = 0;
+
+    while (!in.eof()) {
+        in >> data[i];
+        i++;
+        
+        if (i >= size) { // reallocate. Where is realloc in C++?
+            size *= 2;
+            int *newdata = new int[size];
+            for (int j = 0; j <= i; j++)
+                newdata[j] = data[j];
+            delete data;
+            data = newdata;
+        }
+    }
+
+    i--;
+    int min = data[0];
+    for (int j = 0; j < i; j++)
+        if (data[j] < min)
+            min = data[j];
+    return min;
+}
diff --git a/mysqrt.cpp b/mysqrt.cpp
index 18bb632..ddcda6f 100644
--- a/mysqrt.cpp
+++ b/mysqrt.cpp
@@ -7,7 +7,7 @@ double mysqrt(double x)
     bool goodenough = false;
     double lastGuess, nextGuess;
 
-    lastGuess = x / 10.0;
+    lastGuess = x / 2;
 
     if (x <= 0)
         return x;
@@ -15,9 +15,9 @@ double mysqrt(double x)
     while (!goodenough) {
         
         nextGuess = (lastGuess + (x / lastGuess)) / 2.0;
+        goodenough = abs(nextGuess - lastGuess) <= 0.00001;
         lastGuess = nextGuess;
 
-        goodenough = abs(nextGuess - lastGuess) <= 0.000000000001;
     }
     return nextGuess;
 }
diff --git a/mysqrt.h b/mysqrt.h
index 459cc99..23ca4a9 100644
--- a/mysqrt.h
+++ b/mysqrt.h
@@ -3,6 +3,8 @@
 #define MYSQRT_H
 
 #include <cmath>
+#include <cstdlib>
+#include <ctime>
 
 double mysqrt(double x);
 
diff --git a/statistics.h b/statistics.h
index e69de29..042e52d 100644
--- a/statistics.h
+++ b/statistics.h
@@ -0,0 +1,17 @@
+
+#ifndef STATISTICS_H
+#define STATISTICS_H
+
+#include <iostream>
+#include <fstream>
+#include <ctime>
+#include <cstdlib>
+
+void write_data(const char *filename, unsigned int N, unsigned int M);
+
+float get_mean(const char *filename);
+float get_minimum(const char *filename);
+float get_maximum(const char *filename);
+float get_mode(const char *filename);
+
+#endif