#include <stdio.h>
#include <stddef.h>
#include <stdarg.h>
#include <stdlib.h>
#include "geostat.h"
#include "pressure.h"



/* total_velocity                                       */
/* Build total velocity                                 */
/* grid: structure defining the grid                    */
/* mean: permeability mean                              */
/* dgradient: macroscopic pressure gradient in wanted direction   */
/* realout: structure defining a X velocity realization */

void total_velocity(struct grid_mod grid,double mean,int direction,struct pressure_mod gradient,struct realization_mod *realout)
{
  int i,j,k,maille0,maille1;
  double temp,grad;
  switch(direction)
    {
    case 1:
      grad = gradient.x/(grid.NX*grid.DX);
      break;
    case 2:
      grad = gradient.y/(grid.NY*grid.DY);/*  *grid.NY*grid.DY; */
      break;
    case 3:
      grad = gradient.z/(grid.NZ*grid.DZ); /* *grid.NZ*grid.DZ; */
      break;
    default :
      printf("build_velocity.c: wrong velocity direction!!! direction: %d\n",direction);
      break;
    }

  /* x velocity reconstruction */
  for ( k = 0; k < grid.NZ; k++) {
    for (j = 0; j < grid.NY; j++) {
      for (i = 0; i < grid.NX; i++) {
	maille1 = i+(j+k*grid.NY)*grid.NX;
	temp=mean*grad+(*realout).vector[maille1];
/* 	temp=mean*grad; */
	(*realout).vector[maille1]=temp;
      }
    }
  }

  return;
}