Fix smuos#2: Add a function median()

mm.c

@@ -21,6 +21,14 @@ float mean(int *num, int length) {
   return sum/length;
 }
 
+float median(int *num, int length){
+  if(length%2==0){
+    return (num[length/2-1]+num[length/2])/(float)2;
+  }else{
+    return num[length/2+1];
+  }
+}
+
 int main(int argc, char *argv[]) {
 
     int i, length, *pt;
@@ -57,6 +65,7 @@ int main(int argc, char *argv[]) {
     }
 
     fprintf(stdout, "\nMean: %f", mean(pt, length));
+    fprintf(stdout, "\nMedian: %f", median(pt, length));
     fprintf(stdout, "\n%s: FIN. \n", argv[0]);
 
     return 0;

mm.c~

@@ -0,0 +1,73 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+#define debug 0
+
+// Comparison function for qsort()
+int numcmp (const void *a, const void *b) {
+    int x = *((int*) a);
+    int y = *((int*) b);
+    if (x > y) return 1;
+    if (x < y) return -1;
+    return 0;
+}
+
+float mean(int *num, int length) {
+  float sum = 0;
+  int i;
+  for(i=0; i<length;i++){
+    sum += num[i];
+  }
+  return sum/length;
+}
+
+float median(int *num, int length){
+  if(length%2==0){
+    return (num[length/2]+num[length/2+1])/(float)2;
+  }else{
+    return num[length/2+1];
+  }
+}
+
+int main(int argc, char *argv[]) {
+
+    int i, length, *pt;
+
+    // Check for proper usage
+    if (argc < 2) {
+        fprintf(stderr, "%s: Aborting, not enough arguments.\n", argv[0]);
+        return (-1);
+    }
+
+    // Determine amount of numbers from argc
+    length = argc - 1;
+#if debug
+    fprintf(stderr, "%s: DEBUG: %d numbers were passed.\n", argv[0], length);
+#endif
+
+    // Allocate memory for array of number (and error check)
+    if ((pt = malloc(length * sizeof(int))) == NULL) {
+        fprintf(stderr, "%s: Could not allocate memory.\n", argv[0]);
+    }
+
+    // Read numbers into array
+    for (i = 0; i < length; i++) {
+        pt[i] = (int) strtol(argv[i+1], NULL, 10);
+    }
+
+    // Sort numbers
+    qsort(pt, length, sizeof(int), numcmp);
+
+    // Print out numbers
+    fprintf(stdout, "%s: Sorted output is: \n", argv[0]);
+    for (i=0; i<length; i++) {
+        fprintf(stdout, "%d ", pt[i]);
+    }
+
+    fprintf(stdout, "\nMean: %f", mean(pt, length));
+    fprintf(stdout, "\nMedian: %f", median(pt, length));
+    fprintf(stdout, "\n%s: FIN. \n", argv[0]);
+
+    return 0;
+
+}