e_time.c
No OneTemporary
Actions

Subscribers

None

File Metadata

	#include<stdio.h>
	#include<math.h>
	#include<fonction.h>
	#include<constant.h>
	#include<dimension.h>
	#include<structure.h>

	/****************************************************************/
	/* nom: e_time */
	/* auteur: Jean-Paul Kneib */
	/* date: 10/02/92 */
	/* place: Toulouse */
	/****************************************************************
	* Return the time delay at point <pi>
	*/
	double e_time(struct point pi, double dlsds)
	{
	const extern struct pot lens[];
	const extern struct g_cosmo C;

	double cst, dl, time;
	struct point gr;

	dl = distcosmo1(lens[0].z);
	cst = (1 + lens[0].z) * dl / dlsds * th_a2_day / C.h; /* time delay in days */

	gr = e_grad(&pi);
	gr.x *= dlsds;
	gr.y *= dlsds;
	time = cst * ((gr.x * gr.x + gr.y * gr.y) / 2. - e_pot(pi, dlsds));

	return(time);
	}