!
! This file is part of SACAMOS, State of the Art CAble MOdels for Spice. 
! It was developed by the University of Nottingham and the Netherlands Aerospace 
! Centre (NLR) for ESA under contract number 4000112765/14/NL/HK.
! 
! Copyright (C) 2016-2018 University of Nottingham
! 
! SACAMOS is free software: you can redistribute it and/or modify it under the 
! terms of the GNU General Public License as published by the Free Software 
! Foundation, either version 3 of the License, or (at your option) any later 
! version.
! 
! SACAMOS is distributed in the hope that it will be useful, but 
! WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
! or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License 
! for more details.
! 
! A copy of the GNU General Public License version 3 can be found in the 
! file GNU_GPL_v3 in the root or at <http://www.gnu.org/licenses/>.
! 
! SACAMOS uses the EISPACK library (in /SRC/EISPACK). EISPACK is subject to 
! the GNU Lesser General Public License. A copy of the GNU Lesser General Public 
! License version can be found in the file GNU_LGPL in the root of EISPACK 
! (/SRC/EISPACK ) or at <http://www.gnu.org/licenses/>.
! 
! The University of Nottingham can be contacted at: ggiemr@nottingham.ac.uk
!
!
! File Contents:
! MODULE cable_module
!   CONTAINS
!     SUBROUTINE reset_external_conductor_model
!     SUBROUTINE read_cable
!     SUBROUTINE write_cable
!     SUBROUTINE deallocate_cable
!
! The following subroutines are also contained in the module via include files:
!
! cable_checks.F90:  SUBROUTINE gt_zero_check
! cable_checks.F90:  SUBROUTINE cylindrical_check
! cable_checks.F90:  SUBROUTINE cylindrical_with_dielectric_check
! cable_checks.F90:  SUBROUTINE coax_with_dielectric_check
! cable_checks.F90:  SUBROUTINE twisted_pair_check
! cable_checks.F90:  SUBROUTINE shielded_twisted_pair_check
! cable_checks.F90:  SUBROUTINE spacewire_check
! cable_checks.F90:  SUBROUTINE rectangular_check
! cable_checks.F90:  SUBROUTINE flex_cable_check
! cable_checks.F90:  SUBROUTINE dielectric_check
! cable_checks.F90:  SUBROUTINE not_FD_dielectric_check
! cable_checks.F90:  SUBROUTINE transfer_impedance_check
! cable_checks.F90:  SUBROUTINE conductivity_check
! cable_checks.F90:  SUBROUTINE surface_impedance_check
! 
! conductor_impedance_model.F90:  SUBROUTINE read_conductor_impedance_model
! conductor_impedance_model.F90:  SUBROUTINE write_conductor_impedance_model
! conductor_impedance_model.F90:  SUBROUTINE evaluate_conductor_impedance_model
! conductor_impedance_model.F90:  SUBROUTINE calculate_Rdc
! conductor_impedance_model.F90:  SUBROUTINE calculate_internal_impedance
! conductor_impedance_model.F90:  SUBROUTINE calculate_internal_impedance_shell
! conductor_impedance_model.F90:  SUBROUTINE calculate_internal_impedance_rectangular
! conductor_impedance_model.F90:  SUBROUTINE ber_bei
! conductor_impedance_model.F90:  SUBROUTINE deallocate_conductor_impedance_model
!
! shielded_twisted_pair_cm_dm_parameter_calculation.F90:  SUBROUTINE shielded_twisted_pair_cm_dm_parameter_calculation
! 
! The following included subroutines relate to individual cable types:
!
! cylindrical.F90:  SUBROUTINE cylindrical_set_parameters
! cylindrical.F90:  SUBROUTINE cylindrical_set_internal_domain_information
! cylindrical.F90:  SUBROUTINE cylindrical_plot
! 
! coax.F90:  SUBROUTINE coax_set_parameters
! coax.F90:  SUBROUTINE coax_set_internal_domain_information
! coax.F90:  SUBROUTINE coax_plot
! 
! twisted_pair.F90:  SUBROUTINE twisted_pair_set_parameters
! twisted_pair.F90:  SUBROUTINE twisted_pair_set_internal_domain_information
! twisted_pair.F90:  SUBROUTINE twisted_pair_plot
! 
! shielded_twisted_pair.F90:  SUBROUTINE shielded_twisted_pair_set_parameters
! shielded_twisted_pair.F90:  SUBROUTINE shielded_twisted_pair_set_internal_domain_information
! shielded_twisted_pair.F90:  SUBROUTINE shielded_twisted_pair_plot
! 
! spacewire.F90:  SUBROUTINE spacewire_set_parameters
! spacewire.F90:  SUBROUTINE spacewire_set_internal_domain_information
! spacewire.F90:  SUBROUTINE spacewire_plot
! 
! twinax.F90:  SUBROUTINE twinax_set_parameters
! twinax.F90:  SUBROUTINE twinax_set_internal_domain_information
! twinax.F90:  SUBROUTINE twinax_plot
! 
! flex_cable.F90:  SUBROUTINE flex_cable_set_parameters
! flex_cable.F90:  SUBROUTINE flex_cable_set_internal_domain_information
! flex_cable.F90:  SUBROUTINE flex_cable_plot
! 
! ML_flex_cable.F90:  SUBROUTINE ML_flex_cable_set_parameters
! ML_flex_cable.F90:  SUBROUTINE ML_flex_cable_set_internal_domain_information
! ML_flex_cable.F90:  SUBROUTINE ML_flex_cable_plot
! 
! Dconnector.F90:  SUBROUTINE Dconnector_set_parameters
! Dconnector.F90:  SUBROUTINE Dconnector_set_internal_domain_information
! Dconnector.F90:  SUBROUTINE Dconnector_plot
! 
! overshield.F90:  SUBROUTINE overshield_set_parameters
! overshield.F90:  SUBROUTINE overshield_set_internal_domain_information
! overshield.F90:  SUBROUTINE overshield_plot
! 
! ground_plane.F90:  SUBROUTINE ground_plane_set_parameters
! ground_plane.F90:  SUBROUTINE ground_plane_set_internal_domain_information
! ground_plane.F90:  SUBROUTINE ground_plane_plot
!
!
! NAME
!     MODULE cable_module
!
!     Data structures and subroutines relating to cables in general 
!     plus subroutines tailerd to individual cable types
!     
! COMMENTS
!     
!
! HISTORY
!    started 25/11/2015 CJS
!    Include multiple domain cables 21/03/2016 CJS
!    Include general conductor impedance model 12/05/2016 CJS
!    put the external condcutor model information into its own structure 6/10/2016 CJS
!     16/11/2017 CJS Include network synthesis process to replace s-domain transfer functions
!     16/3/2018 CJS Add ML_flex_cable
!     24/10/2023 CJS Start to add FastHenry2 stuff
!
MODULE cable_module

USE type_specifications
USE filter_module
USE frequency_spec
USE general_module

IMPLICIT NONE

TYPE:: conductor_impedance_model

! This structure holds the data required to specify a conductor loss model
! parameters for the following conductor loss models are encompassed by this data:
! impedance_model_type_PEC                               
! impedance_model_type_cylindrical_with_conductivity     
! impedance_model_type_filter                            
! impedance_model_type_cylidrical_shell_with_conductivity
! impedance_model_type_cylindrical_shield                
! impedance_model_type_rectangular_with_conductivity    
! impedance_model_type_FH2   

  integer  :: impedance_model_type

  real(dp) :: radius
  real(dp) :: conductivity
  real(dp) :: width
  real(dp) :: height
  real(dp) :: Rdc
  real(dp) :: thickness
  real(dp) :: Resistance_multiplication_factor    ! this is required for the common mode loss in the differential mode/
                                                  ! common mode domain decomposition model of twisted pairs
  
! filter function for impedance_model_type_filter 
  type(Sfilter) :: ZT_filter
  
! parameters for impedance_model_type_transfer_impedance_from_braid_parameters

END TYPE conductor_impedance_model

TYPE:: external_conductor_model

! This structure contains the information to specify the external conductor(s) of a
! cable. This is required for the calculation on the PUL parameters of the external domain
! of the cable.  

  integer  :: conductor_type
  logical  :: conductor_is_shield
  real(dp) :: conductor_radius
  real(dp) :: conductor_sigma
  real(dp) :: conductor_width
  real(dp) :: conductor_width2
  real(dp) :: conductor_height
  real(dp) :: conductor_ox
  real(dp) :: conductor_oy
  real(dp) :: dielectric_radius
  real(dp) :: dielectric_width
  real(dp) :: dielectric_height
  real(dp) :: dielectric_ox
  real(dp) :: dielectric_oy
  type(Sfilter) :: dielectric_epsr

END TYPE external_conductor_model

TYPE::cable_specification_type 

! This structure contains all the information relating to a cable including:
! PUL parameters of internal domains (frequency domain Y, Z matrices plus high frequency L and C matrices)
! The voltage and current  domain transformation matrices
! domain based reference conductors for each conductor
! conductor impedance models
! external conductor models

  character(LEN=line_length)        :: version 
  character(LEN=line_length)        :: cable_name  
  character(LEN=line_length)        :: cable_type_string  
  integer        :: cable_type
  integer        :: tot_n_conductors
  integer        :: tot_n_domains
  integer        :: n_external_conductors
  integer        :: n_internal_conductors
  integer        :: n_internal_domains
  integer        :: n_parameters
  real(dp),allocatable    :: parameters(:)  ! parameters read from the .cable_spec file

! frequency dependent dielectric models read from the .cable_spec file
  integer        :: n_dielectric_filters
  type(Sfilter),allocatable :: dielectric_filter(:)

! transfer impedance models read from the .cable_spec file
  integer        :: n_transfer_impedance_models
  type(Sfilter),allocatable     :: transfer_impedance(:)
  
! conductor numbering information
  integer,allocatable :: local_reference_conductor(:)
  integer,allocatable :: local_domain_n_conductors(:)
  
  integer,allocatable :: global_domain_conductor(:)
  integer,allocatable :: terminal_conductor(:)
  
! Domain transformation matrices
  type(matrix) :: MI
  type(matrix) :: MV
  
! internal domain based information

  integer,allocatable         :: local_domain(:)
  integer,allocatable         :: n_internal_conductors_in_domain(:)
  
! High frequency inductance and capacitance matrices for each internal domain
  type(matrix),allocatable    :: L_domain(:)
  type(matrix),allocatable    :: C_domain(:)

! Frequency dependent impedance and admittance matrices for each internal domain  
  type(Sfilter_matrix),allocatable    :: Z_domain(:)
  type(Sfilter_matrix),allocatable    :: Y_domain(:)

! conductor impedance models for each conductor in the cable 
  type(conductor_impedance_model),allocatable    :: conductor_impedance(:)
                                                    
! external conductor information
  type(external_conductor_model),allocatable     :: external_model(:)
  
! Y matrix element function fitting information for frequency dependent dielectrics
! model order
  integer    :: Y_fit_model_order
      
! frequency range specification for the function fitting for frequency dependent dielectrics
  type(frequency_specification) :: Y_fit_freq_spec
  
  character(LEN=line_length),allocatable   :: conductor_label(:)

END TYPE cable_specification_type

! These constant parameters identify cable types, conductor shapes and impedance model types 

integer,parameter    :: cable_geometry_type_cylindrical              =1
integer,parameter    :: cable_geometry_type_twisted_pair             =2
integer,parameter    :: cable_geometry_type_overshield               =3
integer,parameter    :: cable_geometry_type_coax                     =4
integer,parameter    :: cable_geometry_type_shielded_twisted_pair    =5
integer,parameter    :: cable_geometry_type_spacewire                =6
integer,parameter    :: cable_geometry_type_twinax                   =7
integer,parameter    :: cable_geometry_type_flex_cable               =8
integer,parameter    :: cable_geometry_type_Dconnector               =9
integer,parameter    :: cable_geometry_type_ground_plane             =10 
integer,parameter    :: cable_geometry_type_ML_flex_cable            =11

integer,parameter    :: impedance_model_type_PEC                                =0
integer,parameter    :: impedance_model_type_cylindrical_with_conductivity      =1
integer,parameter    :: impedance_model_type_filter                             =2
integer,parameter    :: impedance_model_type_cylidrical_shell_with_conductivity =3
integer,parameter    :: impedance_model_type_cylindrical_shield                 =4
integer,parameter    :: impedance_model_type_rectangular_with_conductivity      =5
integer,parameter    :: impedance_model_type_FH2                                =6
                       
CONTAINS

! The following include files contain processes specific to individual cable types

include 'cylindrical.F90'
include 'coax.F90'
include 'twisted_pair.F90'
include 'shielded_twisted_pair.F90'
include 'spacewire.F90'
include 'twinax.F90'
include 'flex_cable.F90'
include 'ML_flex_cable.F90'
include 'Dconnector.F90'
include 'overshield.F90'
include 'ground_plane.F90'

! The following subroutines apply to all cable types

include 'cable_checks.F90'
include 'shielded_twisted_pair_cm_dm_parameter_calculation.F90'

! The following include file contains all processes related to the conductor impedance models

include 'conductor_impedance_model.F90'


! NAME
!     SUBROUTINE reset_external_conductor_model
!
!     reset data relating to a cables external conductor model
!     
! COMMENTS
!     
!
! HISTORY
!    started 6/10/2016 CJS
!

  SUBROUTINE reset_external_conductor_model(ext_model)

  USE type_specifications
  USE general_module
  USE maths
  USE filter_module

  IMPLICIT NONE

! variables passed to subroutine

  type(external_conductor_model),intent(OUT)    :: ext_model
  
! local variables

! START

  ext_model%conductor_type=0d0
  ext_model%conductor_is_shield=.FALSE.
  ext_model%conductor_radius=0d0
  ext_model%conductor_sigma=0d0
  ext_model%conductor_width=0d0
  ext_model%conductor_width2=0d0
  ext_model%conductor_height=0d0
  ext_model%conductor_ox=0d0
  ext_model%conductor_oy=0d0
  ext_model%dielectric_radius=0d0
  ext_model%dielectric_width=0d0
  ext_model%dielectric_height=0d0
  ext_model%dielectric_ox=0d0
  ext_model%dielectric_oy=0d0
  ext_model%dielectric_epsr=1d0

END SUBROUTINE reset_external_conductor_model

! NAME
!     SUBROUTINE read_cable(unit)
!
!     read cable structure from a specified unit
!     
! COMMENTS
!     
!
! HISTORY
!    started 2/12/2015 CJS
!

  SUBROUTINE read_cable(cable,file_unit)

  USE type_specifications
  USE general_module
  USE maths
  USE filter_module

  IMPLICIT NONE

! variables passed to subroutine

  type(cable_specification_type),intent(INOUT)  :: cable
  integer,intent(IN)                          :: file_unit
  
! local variables

  character(len=filename_length)    :: filename
  integer        :: i,j,i2,j2
  integer        :: domain
  integer        :: dim
  integer        :: matrix_dimension
    
  logical        :: file_exists
  character(len=line_length)    :: line

! START

! check the existance of the cable file and open it for reading
  filename=trim(MOD_cable_lib_dir)//trim(cable%cable_name)//cable_file_extn

  inquire(file=trim(filename),exist=file_exists)
  if (.NOT.file_exists) then
    run_status='ERROR, Cannot find the required cable file:'//trim(filename)
    CALL write_program_status()
    STOP 1
  end if 
  
! open and read the file
  
  OPEN(unit=cable_file_unit,file=trim(filename))

  if (verbose) write(*,*)'Opened file:',trim(filename)
    
! STAGE_1 this reading process is specific to stage 1 and cylindrical conductors only
  read(cable_file_unit,'(A)',ERR=9000)cable%version
  read(cable_file_unit,'(A)',ERR=9000)cable%cable_type_string
  read(cable_file_unit,*,ERR=9000)cable%cable_type

  read(cable_file_unit,*,ERR=9000)cable%tot_n_conductors
  read(cable_file_unit,*,ERR=9000)cable%n_external_conductors
  read(cable_file_unit,*,ERR=9000)cable%tot_n_domains
  read(cable_file_unit,*,ERR=9000)cable%n_internal_conductors
  read(cable_file_unit,*,ERR=9000)cable%n_internal_domains
    
  read(cable_file_unit,*,ERR=9000)cable%n_parameters
  ALLOCATE( cable%parameters(1:cable%n_parameters) )
  do i=1,cable%n_parameters
    read(cable_file_unit,*,ERR=9000)cable%parameters(i)
  end do
        
! read the frequency dependent dielectric information
  
  read(cable_file_unit,*,ERR=9000)cable%n_dielectric_filters
  if (cable%n_dielectric_filters.GT.0) then  
    ALLOCATE( cable%dielectric_filter(1:cable%n_dielectric_filters) )
    do i=1,cable%n_dielectric_filters
      read(cable_file_unit,*,ERR=9000)    ! comment line
      CALL read_Sfilter(cable%dielectric_filter(i),cable_file_unit)
    end do
  end if

! read the frequency dependent conductor impedance information
  
  read(cable_file_unit,*,ERR=9000)  ! comment line
  ALLOCATE( cable%conductor_impedance(1:cable%tot_n_conductors) )
  do i=1,cable%tot_n_conductors
    CALL read_conductor_impedance_model(cable%conductor_impedance(i),cable_file_unit)
  end do
 
  read(file_unit,*) ! comment line 
  read(file_unit,*)matrix_dimension ! MI matrix dimension
  cable%MI%dim=matrix_dimension
  ALLOCATE( cable%MI%mat(1:matrix_dimension,1:matrix_dimension) ) 
  CALL dread_matrix(cable%MI%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)
    
  read(file_unit,*) ! comment line 
  read(file_unit,*)matrix_dimension ! MV matrix dimension
  cable%MV%dim=matrix_dimension
  ALLOCATE( cable%MV%mat(1:matrix_dimension,1:matrix_dimension) ) 
  CALL dread_matrix(cable%MV%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)

! write the internal impedance and admittance matrices here 
  if ((cable%n_internal_domains).GT.0) then
  
! allocate internal domain information
    ALLOCATE(cable%n_internal_conductors_in_domain(1:cable%n_internal_domains))
    ALLOCATE(cable%L_domain(1:cable%n_internal_domains))
    ALLOCATE(cable%C_domain(1:cable%n_internal_domains))
    ALLOCATE(cable%Z_domain(1:cable%n_internal_domains))
    ALLOCATE(cable%Y_domain(1:cable%n_internal_domains))
    
    do domain=1,cable%n_internal_domains
  
      read(file_unit,*) ! comment line (domain number)
    
      read(file_unit,*)cable%n_internal_conductors_in_domain(domain)
    
      read(file_unit,*) ! comment line 
      read(file_unit,*)matrix_dimension ! L matrix dimension
      cable%L_domain(domain)%dim=matrix_dimension
      ALLOCATE( cable%L_domain(domain)%mat(1:matrix_dimension,1:matrix_dimension) ) 
      CALL dread_matrix(cable%L_domain(domain)%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)
       
      read(file_unit,*) ! comment line 
      read(file_unit,*)matrix_dimension ! C matrix dimension
      cable%C_domain(domain)%dim=matrix_dimension
      ALLOCATE( cable%C_domain(domain)%mat(1:matrix_dimension,1:matrix_dimension) ) 
      CALL dread_matrix(cable%C_domain(domain)%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)

      read(file_unit,*) ! comment line 
      CALL read_Sfilter_matrix( cable%Z_domain(domain),file_unit )
      
      read(file_unit,*) ! comment line 
      CALL read_Sfilter_matrix( cable%Y_domain(domain),file_unit )
   
    end do ! next domain
  
  end if ! there are internal domains
  
! read the local reference conductor information

  ALLOCATE( cable%local_reference_conductor(1:cable%tot_n_conductors) )

  read(file_unit,*)! comment line
  do i=1,cable%tot_n_conductors
    read(file_unit,*)cable%local_reference_conductor(i)
  end do

! read the local domain information 
  read(file_unit,*)! comment line
  ALLOCATE( cable%local_domain_n_conductors(1:cable%tot_n_domains) )
  do i=1,cable%tot_n_domains
    read(file_unit,*)cable%local_domain_n_conductors(i)
  end do
  
  read(file_unit,*)! comment line
  ALLOCATE( cable%external_model(1:cable%n_external_conductors) )
  
  do i=1,cable%n_external_conductors
    read(file_unit,*) cable%external_model(i)%conductor_type
    read(file_unit,*) cable%external_model(i)%conductor_is_shield
    read(file_unit,*) cable%external_model(i)%conductor_radius
    read(file_unit,*) cable%external_model(i)%conductor_sigma
    read(file_unit,*) cable%external_model(i)%conductor_width
    read(file_unit,*) cable%external_model(i)%conductor_width2
    read(file_unit,*) cable%external_model(i)%conductor_height

! format change. This way of reading allows backward compatibility    
    read(file_unit,'(A)')line    
    read(line,*,err=100) cable%external_model(i)%conductor_ox,cable%external_model(i)%conductor_oy
    GOTO 110
100 read(line,*) cable%external_model(i)%conductor_ox
    cable%external_model(i)%conductor_oy=0d0
110 CONTINUE
    
    read(file_unit,*) cable%external_model(i)%dielectric_radius
    read(file_unit,*) cable%external_model(i)%dielectric_width
    read(file_unit,*) cable%external_model(i)%dielectric_height

! format change. This way of reading allows backward compatibility    
    read(file_unit,'(A)')line    
    read(line,*,err=200) cable%external_model(i)%dielectric_ox,cable%external_model(i)%dielectric_oy
    GOTO 210
200 read(line,*) cable%external_model(i)%dielectric_ox
    cable%external_model(i)%dielectric_oy=0d0
210 CONTINUE
   
    CALL read_Sfilter(cable%external_model(i)%dielectric_epsr,cable_file_unit)
  end do
  
! read the conductor labels
  ALLOCATE( cable%conductor_label(1:cable%tot_n_conductors) )
  read(file_unit,*)  ! comment line
  do i=1,cable%tot_n_conductors
    read(file_unit,'(A)')cable%conductor_label(i)
  end do

! Allocate the global domain conductor and termainal conductor information and set to zero as this is
! not known at the cable building stage

  ALLOCATE( cable%global_domain_conductor(1:cable%tot_n_conductors) )
  cable%global_domain_conductor(1:cable%tot_n_conductors)=0

  ALLOCATE( cable%terminal_conductor(1:cable%tot_n_conductors) )
  cable%terminal_conductor(1:cable%tot_n_conductors)=0
  
  CLOSE(unit=cable_file_unit)

  if (verbose) write(*,*)'Closed file:',trim(filename)

  RETURN
  
9000  run_status='ERROR reading the cable file:'//trim(filename)
      CALL write_program_status()
      STOP 1
  
  END SUBROUTINE read_cable

! NAME
!     SUBROUTINE write_cable
!
!     write cable structure to a specified unit
!     
! COMMENTS
!     
!
! HISTORY
!    started 2/12/2015 CJS
!

  SUBROUTINE write_cable(cable,file_unit)

  USE type_specifications
  USE general_module
  USE maths
  USE filter_module

  IMPLICIT NONE

! variables passed to subroutine

  type(cable_specification_type),intent(IN) :: cable
  integer,intent(IN)                        :: file_unit
  
! local variables

  character(len=filename_length)    :: filename
  
  integer                :: i,j
  
  integer                :: domain
  integer                :: matrix_dimension

! START

! open the output (.cable) file

  filename=trim(MOD_cable_lib_dir)//trim(cable%cable_name)//cable_file_extn
  
  if (verbose) write(*,'(A)')'Opening file:',trim(filename)
  
  open(unit=file_unit,file=trim(filename))

! write .cable file
  write(file_unit,'(A)')trim(cable%version)
  write(file_unit,'(A)')trim(cable%cable_type_string)
  write(file_unit,*)cable%cable_type,' # cable type number'
  
  write(file_unit,*)cable%tot_n_conductors,     ' # Total Number of conductors' 
  write(file_unit,*)cable%n_external_conductors,' # Number of external conductors' 
  write(file_unit,*)cable%tot_n_domains,        ' # Total number of domains (including external domain)'
  write(file_unit,*)cable%n_internal_conductors,' # Number of internal conductors' 
  write(file_unit,*)cable%n_internal_domains,   ' # Number of internal domains' 

! Number of external conductor parameters 

  write(file_unit,*)cable%n_parameters,' # Number of cable parameters' 

  do i=1,cable%n_parameters
    write(file_unit,*)cable%parameters(i)
  end do
  
! write the frequency dependent dielectric models
  write(cable_file_unit,*)cable%n_dielectric_filters,' # number of frequency dependent dielectric models'
  do i=1,cable%n_dielectric_filters
    write(cable_file_unit,*)'# Dielectric filter number',i
    CALL write_Sfilter(cable%dielectric_filter(i),cable_file_unit)
  end do
  
! write the frequency dependent conductor impedance models

  write(cable_file_unit,*)'# Conductor impedance models'
  do i=1,cable%tot_n_conductors
    CALL write_conductor_impedance_model(cable%conductor_impedance(i),cable_file_unit)
  end do
  
! write the current and voltage local to global transformation matrices
  
  matrix_dimension=cable%MI%dim
  write(file_unit,*)'External to domain conductor current transformation matrix, MI'
  write(file_unit,*)matrix_dimension,' Dimension of MI'
  CALL dwrite_matrix(cable%MI%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)
  
  matrix_dimension=cable%MV%dim
  write(file_unit,*)'External to domain conductor voltage transformation matrix, MV'
  write(file_unit,*)matrix_dimension,' Dimension of MV'
  CALL dwrite_matrix(cable%MV%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)
 
  if ((cable%n_internal_domains).GT.0) then
    
    do domain=1,cable%n_internal_domains
      
      write(file_unit,*)'Domain number',domain
    
      write(file_unit,*)cable%n_internal_conductors_in_domain(domain),' # number of conductors'
    
! write the internal impedance and admittance matrices here 
  
      matrix_dimension=cable%L_domain(domain)%dim
      write(file_unit,*)'High frequency Per-Unit-length Inductance Matrix, L'
      write(file_unit,*)matrix_dimension,' Dimension of L'
      CALL dwrite_matrix(cable%L_domain(domain)%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)
  
      matrix_dimension=cable%C_domain(domain)%dim
      write(file_unit,*)'High frequency Per-Unit-length Capacitance Matrix, C'
      write(file_unit,*)matrix_dimension,' Dimension of C'
      CALL dwrite_matrix(cable%C_domain(domain)%mat,matrix_dimension,matrix_dimension,matrix_dimension,file_unit)

      write(file_unit,*)'Per-Unit-length Impedance Matrix, Z'
      CALL write_Sfilter_matrix( cable%Z_domain(domain),file_unit )
      
      write(file_unit,*)'Per-Unit-length Admittance Matrix, Y'
      CALL write_Sfilter_matrix( cable%Y_domain(domain),file_unit )

    end do ! next domain

  end if ! there are internal domains 

! write the local reference conductor information
  write(file_unit,*)' # Local reference conductor for internal domains' 
  do i=1,cable%tot_n_conductors
    write(file_unit,*)cable%local_reference_conductor(i)
  end do

! Write the local domain information 
  write(file_unit,*)' # number of conductors in each domain' 
  do i=1,cable%tot_n_domains
    write(file_unit,*)cable%local_domain_n_conductors(i)
  end do
  
  write(file_unit,*)' # External conductor information and dielectric model' 
  do i=1,cable%n_external_conductors
    write(file_unit,*) cable%external_model(i)%conductor_type,'  conductor type'
    write(file_unit,*) cable%external_model(i)%conductor_is_shield,'  conductor_is_shield flag'
    write(file_unit,*) cable%external_model(i)%conductor_radius  ,' conductor_radius '
    write(file_unit,*) cable%external_model(i)%conductor_sigma  ,' conductor_sigma '
    write(file_unit,*) cable%external_model(i)%conductor_width   ,' conductor_width  '
    write(file_unit,*) cable%external_model(i)%conductor_width2   ,' conductor_width2  '
    write(file_unit,*) cable%external_model(i)%conductor_height  ,' conductor_height '
    write(file_unit,*) cable%external_model(i)%conductor_ox,cable%external_model(i)%conductor_oy     &
                      ,' conductor_ox,  conductor_oy    '
    write(file_unit,*) cable%external_model(i)%dielectric_radius ,' dielectric_radius'
    write(file_unit,*) cable%external_model(i)%dielectric_width  ,' dielectric_width '
    write(file_unit,*) cable%external_model(i)%dielectric_height ,' dielectric_height'
    write(file_unit,*) cable%external_model(i)%dielectric_ox,cable%external_model(i)%dielectric_oy   &
                      ,' dielectric_ox, dielectric_oy    '
    CALL write_Sfilter(cable%external_model(i)%dielectric_epsr,cable_file_unit)
  end do
 
! write the conductor labels
  write(file_unit,*)' # Conductor labels' 
  do i=1,cable%tot_n_conductors
    write(file_unit,*)trim(cable%conductor_label(i))
  end do

! close .cable file

  CLOSE(unit=file_unit)

  RETURN

  END SUBROUTINE write_cable


! NAME
!     SUBROUTINE deallocate_cable
!
!     deallocate cable structure data
!     
! COMMENTS
!     
!
! HISTORY
!    started 2/12/2015 CJS
!

  SUBROUTINE deallocate_cable(cable)

  USE type_specifications
  USE general_module
  USE filter_module

  IMPLICIT NONE

! variables passed to subroutine

  type(cable_specification_type),intent(INOUT) :: cable
  
! local variables

  integer :: domain
  integer :: parameter
  integer :: i

! START

  if ( allocated(cable%parameters) ) DEALLOCATE( cable%parameters )
  
  if (ALLOCATED(cable%n_internal_conductors_in_domain)) then
    DEALLOCATE(cable%n_internal_conductors_in_domain)
  end if
  
  if (ALLOCATED(cable%L_domain)) then  
    do domain=1,cable%n_internal_domains
      DEALLOCATE(cable%L_domain(domain)%mat)
    end do  
    DEALLOCATE(cable%L_domain)
  end if
  
  if (ALLOCATED(cable%C_domain)) then  
    do domain=1,cable%n_internal_domains
      DEALLOCATE(cable%C_domain(domain)%mat)
    end do  
    DEALLOCATE(cable%C_domain)
  end if
  
  if (ALLOCATED(cable%Z_domain)) then  
    do domain=1,cable%n_internal_domains
      CALL deallocate_Sfilter_matrix( cable%Z_domain(domain) )
    end do  
    DEALLOCATE(cable%Z_domain)
  end if
  
  if (ALLOCATED(cable%Y_domain)) then  
    do domain=1,cable%n_internal_domains
      CALL deallocate_Sfilter_matrix( cable%Y_domain(domain) )
    end do  
    DEALLOCATE(cable%Y_domain)
  end if
  
  if (ALLOCATED(cable%MI%mat)) then  
    DEALLOCATE(cable%MI%mat)
  end if
  
  if (ALLOCATED(cable%MV%mat)) then  
    DEALLOCATE(cable%MV%mat)
  end if

  if (ALLOCATED(cable%local_reference_conductor)) then  
    DEALLOCATE(cable%local_reference_conductor)
  end if
  
  if (ALLOCATED(cable%global_domain_conductor)) then  
    DEALLOCATE(cable%global_domain_conductor)
  end if
  
  if (ALLOCATED(cable%terminal_conductor)) then  
    DEALLOCATE(cable%terminal_conductor)
  end if
  
  if (ALLOCATED(cable%local_domain_n_conductors)) then  
    DEALLOCATE(cable%local_domain_n_conductors)
  end if  
  
  if ( ALLOCATED(cable%external_model) ) then
    do i=1,cable%n_external_conductors
      CALL deallocate_Sfilter(cable%external_model(i)%dielectric_epsr)
    end do
    DEALLOCATE ( cable%external_model )
  end if
    
  if (ALLOCATED( cable%dielectric_filter) ) then
    do i=1,cable%n_dielectric_filters
      CALL deallocate_Sfilter(cable%dielectric_filter(i))
    end do
    DEALLOCATE(cable%dielectric_filter)
  end if
  
  if (ALLOCATED( cable%transfer_impedance) ) then
    do i=1,cable%n_transfer_impedance_models
      CALL deallocate_Sfilter(cable%transfer_impedance(i))
    end do
    DEALLOCATE(cable%transfer_impedance)
  end if
  
  if (ALLOCATED( cable%conductor_impedance) ) then
    do i=1,cable%tot_n_conductors
      CALL deallocate_conductor_impedance_model(cable%conductor_impedance(i))
    end do
    DEALLOCATE(cable%conductor_impedance)
  end if
  
  if (ALLOCATED( cable%conductor_label )) then
    DEALLOCATE(cable%conductor_label)
  end if


  RETURN

  END SUBROUTINE deallocate_cable

END MODULE cable_module