anchor.diff:          IF(ISYS.EQ.0) NSYS=1
           IF(ISYS.EQ.1) NSYS=2
           IF(ISYS.EQ.2) NSYS=4
  +On branch master
  +Your branch is up-to-date with 'origin/master'.
  +Changes to be committed:
  +  (use "git reset HEAD <file>..." to unstage)
  +
  +	new file:   .mesh.f90.swp
  +	modified:   mesh.f90
   
           READ(3,*)   NELEMF
       
  
positive.code:       !REAL*8  PL_AMP(6),FORAMP
        !REAL*8  FCD_AMR,  FCD_AMI
      
      
      
          OPEN(1, FILE='INPUT/DATIN.txt',      STATUS='OLD') 
          OPEN(2, FILE='INPUT/DATBDMS.txt',    STATUS='OLD') 
          OPEN(3, FILE='INPUT/DATWPMS.txt',    STATUS='OLD')
  
          READ(1,*)      IFWKO
          READ(1,*)      H, AMP, WK, BETA
  
          READ(2,*)   ISYS 
          READ(2,*)   NELEMB, NNB, NNBD, IPOL
  
  
negative.code:     implicit none
      
      real(8),allocatable :: XYZB(:,:),DXYZB(:,:)
      !xyzb => (3,node_id)  node data 
      !dxyzb => (3,nrml_id) derivative data
      integer,allocatable :: NCONB(:,:),NCONDB(:,:)   
      ! nconb => node list body mesh
      ! ncondb => normal list body
      real(8),allocatable :: XYZE(:,:,:),DXYZE(:,:,:),TXYZE(:,:,:)
      ! xyze =>  used in convsb, new full mesh for node (3,8,elem_id)
      ! dxyze => used in convsb, new full mesh for normal (3,8,elem,id)
      real(8),allocatable :: XYZTP(:,:),DXYZTP(:,:)
      ! xyztp => convsb, combined node mesh, xyztp(3,node_id)
      ! dxyztp = > combined normal mesh, dxyztp(3,nrml_id)
      integer,allocatable :: NCN(:),NCON(:,:),NCOND(:,:),IETYPE(:)
      ! ncn => elem_type ,namely, the node number in a elem
      ! ncon => combined node list,ncon(8,elem_id)
      ! ncond => combined nrml list,ncond(8,elem_id)
      ! ietype => flag show if a elem is free surface mesh or a body mesh
      integer,allocatable :: NNORMN(:)
      integer :: nsys,nelem,nnode,nnoded,isys
      ! nsys => about symmetr
      ! nelem => elem number in combined mesh
      ! nnode => node number in combined mesh
      ! nnoded => nrml nmber in combined mesh
      integer :: nelemb,nnb,nnbd,nelemf,nnf
      ! nelemb => elem num in body
      ! nnb => node num  in body 
      ! nnbd => nrml num in body
      ! nelemf => elem num in fs
      ! nnf => node num in fs
      
      real(8),protected :: wk,h,beta,amp
      ! wave information
  contains
  
      subroutine read_mesh()
  