Added missing file

src/Davidson/NEEDED_CHILDREN_MODULES

@@ -0,0 +1 @@
+Determinants

src/Davidson/guess_lowest_state.irp.f

@@ -0,0 +1,162 @@
+program first_guess
+  use bitmasks
+  implicit none
+  BEGIN_DOC
+  ! Select all the determinants with the lowest energy as a starting point.
+  END_DOC
+  integer                        :: i,j
+  double precision, allocatable  :: orb_energy(:)
+  double precision               :: E
+  integer, allocatable           :: kept(:)
+  integer                        :: nelec_kept(2)
+  character                      :: occ_char, keep_char
+  
+  PROVIDE H_apply_buffer_allocated psi_det
+  allocate (orb_energy(mo_tot_num), kept(0:mo_tot_num))
+  nelec_kept(1:2) = 0
+  kept(0) = 0
+
+  print *,  'Orbital energies'
+  print *,  '================'
+  print *,  ''
+  do i=1,mo_tot_num
+    keep_char = ' '
+    occ_char = '-'
+    orb_energy(i) = mo_mono_elec_integral(i,i)
+    do j=1,elec_beta_num
+      if (i==j) cycle
+      orb_energy(i) += mo_bielec_integral_jj_anti(i,j)
+    enddo
+    do j=1,elec_alpha_num
+      orb_energy(i) += mo_bielec_integral_jj(i,j)
+    enddo
+    if ( (orb_energy(i) > -.5d0).and.(orb_energy(i) < .1d0) ) then
+      kept(0) += 1
+      keep_char = 'X'
+      kept( kept(0) ) = i
+      if (i <= elec_beta_num) then
+        nelec_kept(2) += 1
+      endif
+      if (i <= elec_alpha_num) then
+        nelec_kept(1) += 1
+      endif
+    endif
+    if (i <= elec_alpha_num) then
+      if (i <= elec_beta_num) then
+        occ_char = '#'
+      else
+        occ_char = '+'
+      endif
+    endif
+    print '(I4, 3X, A, 3X, F10.6, 3X, A)', i, occ_char, orb_energy(i), keep_char 
+  enddo
+
+  
+  integer, allocatable           :: list  (:,:)
+  integer(bit_kind), allocatable :: string(:,:)
+  allocate ( list(N_int*bit_kind_size,2), string(N_int,2) )
+
+  string = ref_bitmask
+  call bitstring_to_list( string(1,1), list(1,1), elec_alpha_num, N_int)
+  call bitstring_to_list( string(1,2), list(1,2), elec_beta_num , N_int)
+
+  psi_det_alpha_unique(:,1) = string(:,1)
+  psi_det_beta_unique (:,1) = string(:,2)
+  N_det_alpha_unique = 1
+  N_det_beta_unique  = 1
+
+  integer :: i1,i2,i3,i4,i5,i6,i7,i8,i9
+
+  psi_det_size = kept(0)**(nelec_kept(1)+nelec_kept(2))
+  print *,  kept(0), nelec_kept(:)
+  call write_int(6,psi_det_size,'psi_det_size')
+  TOUCH psi_det_size
+
+BEGIN_SHELL [ /usr/bin/python ]
+
+template_alpha_ext = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_alpha_num-%(i)d,1) = kept(%(i2)s)
+  call list_to_bitstring( string(1,1), list(1,1), elec_alpha_num, N_int)
+"""
+
+template_alpha = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_alpha_num-%(i)d,1) = kept(%(i2)s)
+  call list_to_bitstring( string(1,1), list(1,1), elec_alpha_num, N_int)
+  N_det_alpha_unique += 1
+  psi_det_alpha_unique(:,N_det_alpha_unique) = string(:,1)
+"""
+
+template_beta_ext = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_beta_num-%(i)d,2) = kept(%(i2)s)
+  call list_to_bitstring( string(1,2), list(1,2), elec_beta_num, N_int)
+"""
+template_beta = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_beta_num-%(i)d,2) = kept(%(i2)s)
+  call list_to_bitstring( string(1,2), list(1,2), elec_beta_num, N_int)
+  N_det_beta_unique += 1
+  psi_det_beta_unique(:,N_det_beta_unique) = string(:,2)
+"""
+
+def write(template_ext,template,imax):
+    print "case(%d)"%(imax)
+    def aux(i2,i1,i,j):
+        if (i==imax-1):
+          print template%locals()
+        else:
+          print template_ext%locals()
+        i += 1
+        j -= 1
+        if (i != imax):
+            i1 = "i%d"%(i)
+            i2 = "i%d"%(i+1)
+            aux(i2,i1,i,j)
+        print "enddo"
+
+    i2 = "i1"
+    i1 = "kept(0)+1"
+    i  = 0
+    aux(i2,i1,i,imax)
+
+def main():
+    print """
+    select case (nelec_kept(1))
+      case(0)
+        continue
+    """
+    for imax in range(1,10):
+        write(template_alpha_ext,template_alpha,imax)
+
+    print """
+    end select
+
+    select case (nelec_kept(2))
+      case(0)
+        continue
+    """
+    for imax in range(1,10):
+        write(template_beta_ext,template_beta,imax)
+    print "end select"
+
+main()
+
+END_SHELL
+
+  TOUCH N_det_alpha_unique N_det_beta_unique psi_det_alpha_unique psi_det_beta_unique
+  call create_wf_of_psi_bilinear_matrix(.False.)
+  call diagonalize_ci
+  j= N_det
+  do i=1,N_det
+    if (psi_average_norm_contrib_sorted(i) < 1.d-6) then
+       j = i-1
+       exit
+    endif
+!  call debug_det(psi_det_sorted(1,1,i),N_int)
+  enddo
+  call save_wavefunction_general(j,N_states,psi_det_sorted,size(psi_coef_sorted,1),psi_coef_sorted)
+
+  deallocate(orb_energy, kept, list, string)
+end