/* ------------------------------------------------------------------------ * This program illustrates an array-based algorithm for tallying a  * continuous-data histogram for data read from standard input (stdin). * Like program uvs, a compiled version of this program supports file * redirection. * * The MIN, MAX, K parameters are "tuned" to the datafile uvs.dat. * For other datafiles these parameters must be adjusted -- you might * want to process the datafile with program uvs first to get a handle on * appropriate values for these three parameters. *  * Name              : Cdh.java  (Continuous Data Histogram) * Authors           : Steve Park & Dave Geyer * Translated by     : Jun Wang * Language          : Java * Latest Revision   : 6-16-06 * ------------------------------------------------------------------------  */import java.io.*;import java.util.*;import java.text.*;class Outliers {  long lo;  long hi;}class Cdh {  static double MIN   = 0.0;  static double MAX   = 8.0;  static int    K     = 16;                        /* number of histogram bins   */  static double DELTA = ((MAX - MIN) / K);         /* histogram bin size (width) */  public static void main(String[] args) throws IOException {    double x;                                      /* data value          */    int    j;                                      /* histogram bin index */    long   index    = 0;                           /* sample size         */    long   count[] = new long [K];                 /* bin count           */    double midpoint[] = new double [K];            /* bin midpoint        */    double sum      = 0.0;    double sumsqr   = 0.0;    double mean;    double stdev;    Outliers o = new Outliers();    o.lo = 0;    o.hi = 0;    for (j = 0; j < K; j++) {      count[j] = 0;      midpoint[j] = MIN + (j + 0.5) * DELTA;    }    String line = null;    InputStreamReader r = new InputStreamReader(System.in);    BufferedReader in = new BufferedReader(r);    try {      while ( (line = in.readLine()) != null ) {        x = Double.parseDouble(line);        index++;        if ((x >= MIN) && (x < MAX)) {          j = (int) ((x - MIN) / DELTA);          count[j]++;        }        else if (x < MIN)          o.lo++;        else          o.hi++;      }    } catch (EOFException e) {      System.out.println("Cdh: " + e);    } catch (NumberFormatException nfe) {//      System.out.println("Cdh: " + nfe);    }    if (index > 0) {      for (j = 0; j < K; j++)                        /* histogram mean */        sum += midpoint[j] * count[j];      mean   = sum / index;      for (j = 0; j < K; j++)                        /* histogram stdev */        sumsqr += Math.pow((midpoint[j] - mean), 2) * count[j];      stdev     = Math.sqrt(sumsqr / index);      DecimalFormat f = new DecimalFormat("###0.000");      System.out.println("bin\tmidpoint\tcount\tproportion\tdensity\n");      for (j = 0; j < K; j++) {         System.out.print((j + 1) + "\t");                         /* bin        */        System.out.print(f.format(midpoint[j]) + "\t\t");                   /* midpoint   */        System.out.print(count[j] + "\t");                        /* count      */        System.out.print(f.format((double) count[j] / index) + "\t\t");     /* proportion */        System.out.println(f.format((double) count[j] / (index * DELTA)));  /* density    */      }      System.out.println("\nsample size .... = " + index);      System.out.println("mean ........... = " + f.format(mean));      System.out.println("stdev .......... = " + f.format(stdev) + "\n");      if (o.lo > 0)        System.out.println("NOTE: there were " + o.lo + " low outliers");      if (o.hi > 0)        System.out.println("NOTE: there were " + o.hi + " high outliers");    }  }}