1 #include <fcntl.h> 2 #include <sys/ioctl.h> 3 #include <stdio.h> 4 #include <sys/time.h> 5 #include <sys/types.h> 6 #include <sys/mman.h> 7 #include <unistd.h> 8 #include <stdlib.h> 9 #include <math.h> 10 11 char *pname; 12 char *in_file; 13 14 #define DATA_COUNT (1024*1024) 15 u_int64_t data_items[DATA_COUNT]; 16 17 int num_data_items = 0; 18 19 #define BUFSIZE 1024 20 char in_buf[BUFSIZE]; 21 22 static int 23 compare_long(const void *p1, const void *p2) 24 { 25 u_int64_t val1 = *(u_int64_t *)p1; 26 u_int64_t val2 = *(u_int64_t *)p2; 27 28 if (val1 == val2) 29 return 0; 30 if (val1 < val2) 31 return -1; 32 return 1; 33 } 34 35 int 36 main(int argc, char **argv) 37 { 38 FILE *in_fp; 39 u_int64_t sum_x = 0; 40 u_int64_t sum_sq_x = 0; 41 u_int64_t mean; 42 double std_dev; 43 int i; 44 int one_sd = 0; 45 int two_sd = 0; 46 int three_sd = 0; 47 double one_sd_low, one_sd_high; 48 double two_sd_low, two_sd_high; 49 double three_sd_low, three_sd_high; 50 51 pname = argv[0]; 52 if (argc == 1) 53 in_fp = stdin; 54 else { 55 in_file = argv[1]; 56 in_fp = fopen(in_file, "r"); 57 } 58 while (fgets(in_buf, BUFSIZE, in_fp)) { 59 if (num_data_items == DATA_COUNT) { 60 fprintf(stderr, 61 "DATA overflow, increase size of data_items array\n"); 62 exit(1); 63 } 64 sscanf(in_buf, "%ju", &data_items[num_data_items]); 65 #if 0 66 printf("%lu\n", data_items[num_data_items++]); 67 #endif 68 num_data_items++; 69 } 70 if (num_data_items == 0) { 71 fprintf(stderr, "Empty input file ?\n"); 72 exit(1); 73 } 74 #if 0 75 printf("Total items %lu\n", num_data_items); 76 #endif 77 for (i = 0 ; i < num_data_items ; i++) { 78 sum_x += data_items[i]; 79 sum_sq_x += data_items[i] * data_items[i]; 80 } 81 mean = sum_x / num_data_items; 82 printf("\tMean %lu\n", mean); 83 std_dev = sqrt((sum_sq_x / num_data_items) - (mean * mean)); 84 printf("\tStd Dev %.2f (%.2f%% of mean)\n", 85 std_dev, (std_dev * 100.0) / mean); 86 one_sd_low = mean - std_dev; 87 one_sd_high = mean + std_dev; 88 two_sd_low = mean - (2 * std_dev); 89 two_sd_high = mean + (2 * std_dev); 90 three_sd_low = mean - (3 * std_dev); 91 three_sd_high = mean + (3 * std_dev); 92 for (i = 0 ; i < num_data_items ; i++) { 93 if (data_items[i] >= one_sd_low && 94 data_items[i] <= one_sd_high) 95 one_sd++; 96 if (data_items[i] >= two_sd_low && 97 data_items[i] <= two_sd_high) 98 two_sd++; 99 if (data_items[i] >= three_sd_low && 100 data_items[i] <= three_sd_high) 101 three_sd++; 102 } 103 printf("\tWithin 1 SD %.2f%%\n", 104 ((double)one_sd * 100) / num_data_items); 105 printf("\tWithin 2 SD %.2f%%\n", 106 ((double)two_sd * 100) / num_data_items); 107 printf("\tWithin 3 SD %.2f%%\n", 108 ((double)three_sd* 100) / num_data_items); 109 printf("\tOutside 3 SD %.2f%%\n", 110 ((double)(num_data_items - three_sd) * 100) / num_data_items); 111 /* Sort the data to get percentiles */ 112 qsort(data_items, num_data_items, sizeof(u_int64_t), compare_long); 113 printf("\t50th percentile %lu\n", data_items[num_data_items / 2]); 114 printf("\t75th percentile %lu\n", data_items[(3 * num_data_items) / 4]); 115 printf("\t90th percentile %lu\n", data_items[(9 * num_data_items) / 10]); 116 printf("\t99th percentile %lu\n", data_items[(99 * num_data_items) / 100]); 117 } 118 119
