/*extin do extinction of incident continuum as set by extinguish command */
#include "cddefines.h"
#include "rfield.h"
#include "extinc.h"
#include "sexp.h"
#include "ipoint.h"
#include "extin.h"

void extin(float *ex1ryd)
{
	long int i, 
	  low;
	double absorb, 
	  factor;

#	ifdef DEBUG_FUN
	fputs( "<+>extin()\n", debug_fp );
#	endif


	/* modify input continuum by leaky absorber
	 * power law fit to Cruddace et al. 1974 ApJ 187, 497.
	 * */
	if( extinc.excolm == 0. )
	{
		*ex1ryd = 1.;
	}
	else
	{

		absorb = 1. - extinc.exleak;
		factor = extinc.excolm*6.22e-18;
		/* extinction at 1 and 4 Ryd */
		*ex1ryd = (float)(extinc.exleak + absorb*sexp(factor));

		low = ipoint(extinc.exlow);
		for( i=low-1; i < rfield.nflux; i++ )
		{
			rfield.flux[i] *= (float)(extinc.exleak + absorb*sexp(factor*
			  (pow(rfield.anu[i],-2.43))));
		}

	}


#	ifdef DEBUG_FUN
	fputs( " <->extin()\n", debug_fp );
#	endif
	return;
}