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/*! \file cluster.cpp

 *

 * \brief Implementation of the calculation for a cluster of spheres.

 */

#include <cstdio>

#include <complex>

/*! \file np_sphere.cpp

/*! \file np_cluster.cpp

 *

 * \brief Cluster of spheres scattering problem handler.

 *

 * This program emulates the execution work-flow originally handled by the

 * FORTRAN EDFB and CLU codes, which undertook the task of solving the

 * scattering calculation for the case of a cluster of spheres, with one or

 * more materials. The program is designed to work in two modes: emulation and

 * enhanced. The emulation mode is activated by invoking the program without

 * arguments. In this case, the code looks for hard-coded default input and

 * writes output in the execution folder, replicating the behaviour of the

 * original FORTRAN code. Advanced mode, instead, is activated by passing

 * command line arguments that locate the desired input files and a valid

 * folder to write the output into. The emulation mode is useful for testing,

 * while the advanced mode implements the possibility to change input and

 * output options, without having to modify the code.

 */

#include <cstdio>

 * or some otherwise formatted configuration data set. The code can be

 * linked to a luncher script or to a GUI oriented application that performs

 * the configuration and runs the main program.

 *

 * \param argc: `int` The number of arguments given in command-line.

 * \param argv: `char **` The vector of command-line arguments.

 * \return result: `int` An exit code passed to the OS (0 for succesful execution).

 */

int main(int argc, char **argv) {

  	string config_file = "../../test_data/cluster/DEDFB";

/*! \file Configuration.h

 *

 * \brief Configuration data structures.

 *

 * To handle the calculation of a scattering problem, the code needs a set

 * of configuration parameters that define the properties of the scattering

 * particle, of the incident radiation field and of the geometry of the

 * problem. The necessary information is managed through the use of two

 * classes: `ScattererConfiguration` and `GeometryConfiguration`. The first

 * class, `ScattererConfiguration`, undertakes the role of describing the

 * scattering particle properties, by defining its structure in terms of a

 * distribution of spherical sub-particles, and the optical properties of

 * the constituting materials. It also defines the scaling vector, which

 * tracks the ratio of particle size and radiation wavelength, eventually

 * allowing for the iteration of the calculation on different wavelengths.

 * Multiple materials and layered structures are allowed, while sphere

 * compenetration is not handled, due to the implied discontinuity on the

 * spherical symmetry of the elementary sub-particles. The second class,

 * `GeometryConfiguration`, on the contrary, describes the properties of

 * the radiation field impinging on the particle. It defines the incoming

 * radiation polarization state, the incident direction and the scattering

 * directions that need to be accounted for. Both classes expose methods to

 * read the required configuration data from input files formatted according

 * to the same rules expected by the original code. In addition, they offer

 * perform I/O operations towards proprietary and standard binary formats.

 */

#ifndef INCLUDE_CONFIGURATION_H_

/*! \file List.h

 *

 * \brief A library of classes used to manage dynamic lists.

 */

#ifndef INCLUDE_LIST_H_

/*! \file Parsers.h

 *

 * \brief A library of functions designed to parse formatted input

 * into memory.

 */

#ifndef FILE_NOT_FOUND_ERROR