
/** @file  psStats.h
 *  \brief basic statistical operations
 *  @ingroup Stats
 *
 *  This file will hold the definition of the histogram and stats data
 *  structures.  It also contains prototypes for procedures which operate
 *  on those data structures.
 *
 *  @author George Gusciora, MHPCC
 *
 *  @version $Revision: 1.31 $ $Name: not supported by cvs2svn $
 *  @date $Date: 2004-10-06 20:07:04 $
 *
 *  Copyright 2004 Maui High Performance Computing Center, University of Hawaii
 */
#if !defined(PS_STATS_H)
#define PS_STATS_H

#include "psVector.h"

/// @addtogroup Stats
/// @{

/******************************************************************************
    Statistical functions and data structures.
 *****************************************************************************/

/** enumeration of statistical calculation options
 *
 *  @see psStats, psVectorStats, psImageStats
 */
// XXX: Is PS_STAT_ROBUST_FOR_SAMPLE obsolete?
typedef enum {
    PS_STAT_SAMPLE_MEAN = 0x000001,
    PS_STAT_SAMPLE_MEDIAN = 0x000002,
    PS_STAT_SAMPLE_STDEV = 0x000004,
    PS_STAT_SAMPLE_QUARTILE = 0x000008,
    PS_STAT_ROBUST_MEAN = 0x000010,
    PS_STAT_ROBUST_MEDIAN = 0x000020,
    PS_STAT_ROBUST_MODE = 0x000040,
    PS_STAT_ROBUST_STDEV = 0x000080,
    PS_STAT_ROBUST_QUARTILE = 0x000100,
    PS_STAT_CLIPPED_MEAN = 0x000200,
    PS_STAT_CLIPPED_STDEV = 0x000400,
    PS_STAT_MAX =  0x000800,
    PS_STAT_MIN =  0x001000,
    PS_STAT_USE_RANGE =  0x002000,
    PS_STAT_USE_BINSIZE = 0x004000,
    PS_STAT_ROBUST_FOR_SAMPLE = 0x008000
} psStatsOptions;

/** This is the generic statistics structure.  It contails the data members
    for the various statistic values.  It also contains the options member to
    specifiy which statistics should be calculated. */
typedef struct
{
    double sampleMean;          ///< formal mean of sample
    double sampleMedian;        ///< formal median of sample
    double sampleStdev;         ///< standard deviation of sample
    double sampleUQ;            ///< upper quartile of sample
    double sampleLQ;            ///< lower quartile of sample
    double robustMean;          ///< robust mean of array
    double robustMedian;        ///< robust median of array
    double robustMode;          ///< Robust mode of array
    double robustStdev;         ///< robust standard deviation of array
    double robustUQ;            ///< robust upper quartile
    double robustLQ;            ///< robust lower quartile
    int robustN50;              ///<
    int robustNfit;             ///<
    double clippedMean;         ///< Nsigma clipped mean
    double clippedStdev;        ///< standard deviation after clipping
    int clippedNvalues;         ///< ???
    double clipSigma;           ///< Nsigma used for clipping; user input
    int clipIter;               ///< Number of clipping iterations; user input
    double min;                 ///< minimum data value in array
    double max;                 ///< maximum data value in array
    double binsize;             ///<
    psStatsOptions options;     ///< bitmask of calculated values
}
psStats;

/** Performs statistical calculations on a vector.
 *
 *  @return psStats*    the statistical results as specified by stats->options
 */
psStats* psVectorStats(
    psStats* stats,    ///< stats structure defines stats to be calculated and how
    psVector* in,    ///< Vector to be analysed: must be F32
    psVector* mask,    ///< Ignore elements where (maskVector & maskVal) != 0: must be INT or NULL
    unsigned int maskVal    ///< Only mask elements with one of these bits set in maskVector
);

/** Allocator of the psStats structure.
 *
 *  @return psStats*    A new psStats struct with the options member set to the
 *                      value given.
 */
psStats* psStatsAlloc(
    psStatsOptions options             ///< Statistics to calculate
);

/******************************************************************************
    Histogram functions and data structures.
 *****************************************************************************/

/** The basic histogram structure which contains bounds and bins.
 *
 *  In this structure, the vector bounds specifies the boundaries of the 
 *  histogram bins, and must of type psF32, while nums specifies the number 
 *  of entries in the bin, and must of type psU32. The value of bounds.n must 
 *  therefore be 1 greater than than nums.n. The two values minNum and maxNum 
 *  are the number of data values which fell below the lower limit bound or 
 *  above the upper limit bound, respectively.
 */
typedef struct
{
    psVector* bounds;                  ///< Bounds for the bins (type F32)
    psVector* nums;                    ///< Number in each of the bins (INT)
    int minNum;                        ///< Number below the minimum
    int maxNum;                        ///< Number above the maximum
    bool uniform;                      ///< Is it a uniform distribution?
}
psHistogram;

/** Allocator for psHistogram where the bounds of the bins are implicitly
 *  specified through simply specifying an upper and lower limit along with 
 *  the size of the bins. 
 *
 *  @return psHistogram*    Newly allocated psHistogram
 */
psHistogram* psHistogramAlloc(
    float lower,                       ///< Lower limit for the bins
    float upper,                       ///< Upper limit for the bins
    int n                              ///< Number of bins
);

/** Allocator for psHistogram where the bounds of the bins are explicitly
 *  specified. 
 *
 *  @return psHistogram*    Newly allocated psHistogram
 */
psHistogram* psHistogramAllocGeneric(
    const psVector* restrict bounds    ///< Bounds for the bins
);

/** Calculate a histogram
 *
 *  The following function populates the histogram bins from the specified 
 *  vector (in). It alters and returns the histogram out structure. The input
 *  vector may be of types psU8, psU16, psF32, psF64.
 *
 *  @return psHistogram*   histogram result
 */
psHistogram* psVectorHistogram(
    psHistogram* out,                  ///< Histogram data
    const psVector* restrict in,       ///< Vector to analyse
    const psVector* restrict mask,     ///< Mask dat for input vector
    unsigned int maskVal               ///< Mask value
);

/** Extracts the statistic value specified by stats->options.
 *
 *  @return bool    If more than one statistic result is set in stats->options,
 *                  false is returned and the value parameter is not set, 
 *                  otherwise true is returned.
 */
bool p_psGetStatValue(
    const psStats* stats,
    ///< the statistic struct to operate on

    double *value
    ///< if return is true, this is set to the specified statistic value by stats->options
);


void p_psNormalizeVector(psVector* myData);

void p_psNormalizeVectorF64(psVector* myData);

/// @}

#endif
