ifalgama.c

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//
// IFALGAMA     : log of gamma function for REAL argument
//

#include "fmath.h"
#include <float.h>

#include "ftnstd.h"
#include "ifenv.h"

extern  extended          __lgamma(extended,const extended __FAR *);

static  const extended  __FAR xinf = { FLT_MAX };
static  const single    __FAR big = { 4.03e+36 };


single ALGAMA( single arg ) {
//===========================

    if( fabs( arg ) >= big ) return( xinf );
    if( arg == 0.0 ) return( xinf );
    return( __lgamma( arg, &xinf ) );
}

single XALGAMA( single *arg ) {
//=============================

    return( ALGAMA( *arg ) );
}