c_pxhiss - Accumulates values in a histogram array with a skip factor

SYNTAX

#include "worgen.h"

FUNCTION c_pxhiss (ns, buf, dtype, hist, count, skip)

     long               *ns;
     unsigned char      *buf;
     long               *dtype;
     long               *hist;
     long               *count;
     long               *skip;

PARAMETERS

ns (input, integer)

The number of samples in the input buffer to be histogrammed.

buf (input, 'dtype')

An input array of pixel values to be histogrammed.

dtype (input, integer)

An integer value that represents the type of data to be histogrammed. Legal values include:

     = EBYTE(1):     unsigned byte data
     = EWORD(2):     signed two byte data
     = ELONG(3):     signed four byte data
     = EREAL(4):     four byte floating point data

hist (output, 'dtype')

The histogram array to be accumulated. The histogram array must be initialized to zero at the start of processing in the application program. For real data, the array must be dimensioned to [16384,2] in the application program.

count (output, integer)

The total number of values the histogram array contains. Only returned for real*4 and integer*4 data. Note that the count must be initialized to zero at the start of processing in the application program.

skip (input, integer)

The number of samples to be skipped. Only every skip sample will be histogrammed.

DESCRIPTION

The c_pxhiss() call is used to create a histogram array hist from every skip value from ns samples of a pixel array buf of type dtype. The array will contain count number of values.

RETURN VALUE

c_pxhiss() returns

     E_SUCC -->  successful completion 
     TYPERR -->  invalid data type specified
     E_FAIL -->  failure