#include <iostream>

#include <BoxLib.H>

#include <MultiFab.H>

#include <BLFort.H>

// declare a fortran subroutine

extern "C"

{

void work(const int* lo, const int* hi, BL_FORT_FAB_ARG(dfab));

}

int main(int argc, char* argv[])

{

BoxLib::Initialize(argc,argv);

// define the lower and upper corner of a 3D domain

IntVect domain_lo(0 , 0, 0);

IntVect domain_hi(63,63,63);

// build a box for the domain

Box domain(domain_lo, domain_hi);

// build a box array from the 64^3 domain box

BoxArray ba(domain);

// break the box array into 32^3 boxes

ba.maxSize(32);

// build a multifab on the box array with 1 component, 0 ghost cells

MultiFab data(ba, 1, 0);

// loop over boxes and do some work

for (MFIter mfi(data); mfi.isValid(); ++mfi)

{

const Box& bx = mfi.validbox(); // box for this fab

// call a fortran subroutine

work(bx.loVect(), bx.hiVect(),

BL_TO_FORTRAN(data[mfi]));

}

// print some information for checking

/* I got

min = 7.945268926e-11

max = 1

max norm = 1

L1 norm = 8680.319857

L2 norm = 56.24354515

*/

std::cout << "min = " << data.min(0) << std::endl;

std::cout << "max = " << data.max(0) << std::endl;

std::cout << "max norm = " << data.norm0() << std::endl;

std::cout << "L1 norm = " << data.norm1() << std::endl;

std::cout << "L2 norm = " << data.norm2() << std::endl;

BoxLib::Finalize();

}