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// @(#) $Revision: 4.5 $ $Source: /judy/src/apps/demo/funhist.c $
//
// FUNCTION HISTOGRAM; JUDYL DEMO PROGRAM
//
// This program uses JudyL to create a histogram of data generated by the
// function random(3M).  Other functions could be substituted in.
//
// The program generates n random numbers, stores them in a JudyL array
// and then prints a histogram.  All aspects of the generation and
// histogram are timed so the user can see how long various JudyL functions
// take.
//
//
// This demonstrates:
//           JLI        (JudyLIns)
//           JLF        (JudyLFirst)
//           JLL        (JudyLLast)
//           JLN        (JudyLNext)
//           JLC        (JudyLCount)
//           JLBC       (JudyLByCount)
//           how to access a JudyL value.
//
// Notice that using JudyL gives you fast stores and lookups as with hashing
// but without having to define a hash function, initialize the hash table
// or having to predetermine a good hash table size.  It also gives you a
// sorted list at the same time.
// Also notice that JudyLCount is much faster than you can sequentially
// count items in an array.
//

#include <stdlib.h>     // random()
#include <stdio.h>      // printf()
#include <sys/time.h>   // gettimeofday()
#include <Judy.h>       // JL*() routines

// Default number of iterations (number of random numbers generated)
// This may be overridden on the command line

#define DEFAULT_ITER 1000000

// The number of buckets the histogram is divided into.

#define DEFAULT_HISTO_BUCKETS 32

// Macro for correction english output for plurals

#define	PLURAL(count) ((count == 1) ? "" : "s")

// timing routines

struct timeval TBeg, TEnd;
#define STARTTm         gettimeofday(&TBeg, NULL)
#define ENDTm           gettimeofday(&TEnd, NULL)
#define DeltaUSec                                       \
        ((double)(TEnd.tv_sec - TBeg.tv_sec) * 1E6 +    \
         (TEnd.tv_usec - TBeg.tv_usec))

// End of timing routines

int
main(int argc, char **argv)
{
    Pvoid_t   PJArray = NULL;   // main JudyL array
                                // key is random number, value is repeat count
    Pvoid_t   PJCount = NULL;   // second JudyL array
                                // key is repeat count (from PJArray)
                                // value is count of items with the same
                                // repeat count
    Word_t    Index;            // index in JudyLFirst/Next loop
    PWord_t   PValue;           // pointer to Judy array value
    PWord_t   PGenCount;        // pointer to generation count
    Word_t    num_vals;         // number of randoms to generate
    Word_t    iter;             // for loop iteration
    Word_t    unique_nums;      // number of unique randoms generated
    Word_t    random_num;       // random number
    Word_t    median;           // random number
    Word_t    tmp1, tmp2;       // temporary variable
    double    random_gen_time;  // time to generate random numbers
    Word_t    histo_incr;       // histogram increment
    unsigned long long ran_sum = 0; // sum of all generated randoms

// TITLE

    printf("\nJudyL demonstration: random(3M) histogram\n");

// SET NUMBER OF RANDOMS TO GENERATE

    if (argc != 2)
    {
        // SET TO DEFAULT_ITER
        num_vals = DEFAULT_ITER;
        printf("Usage: %s [numvals]\n", argv[0]);
        printf("  Since you did not specify a number of values, %ld\n",
               num_vals);
        printf("  will be used as the number of random numbers to insert\n");
        printf("  into the Judy array\n");
    }
    else
    {
// OVERRIDE NUMBER OF RANDOMS TO GENERATE

        num_vals = atol(argv[1]);
    }

// TIME THE GENERATION OF ALL THE RANDOM NUMBERS.  THIS TIME IS LATER