From 69c7db0689bebfedca57b1783fdeb9129aa38251 Mon Sep 17 00:00:00 2001
From: calandra <calandra@c92efa57-630b-4861-b058-cf58834340f0>
Date: Wed, 22 Jul 2015 09:40:46 +0000
Subject: [PATCH] This routine select n and l of the initial state.

O. Bunau and MCB


git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@11630 c92efa57-630b-4861-b058-cf58834340f0
---
 XSpectra/src/select_nl_init.f90 | 71 +++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 XSpectra/src/select_nl_init.f90

diff --git a/XSpectra/src/select_nl_init.f90 b/XSpectra/src/select_nl_init.f90
new file mode 100644
index 000000000..f6c059212
--- /dev/null
+++ b/XSpectra/src/select_nl_init.f90
@@ -0,0 +1,71 @@
+subroutine select_nl_init(edge, nl_init, two_edges, n_lanczos)
+  USE kinds, ONLY : DP
+  USE io_global, ONLY : stdout
+  IMPLICIT NONE
+  logical :: two_edges
+  integer :: n_lanczos
+  integer, dimension(2) :: nl_init
+  character(LEN=16) :: edge
+  CHARACTER(LEN=10) :: dummy_char, n_0, l_0
+ 
+  if( TRIM(ADJUSTL(edge)) .eq. 'K' ) edge = 'K1'
+  dummy_char = TRIM(ADJUSTL(edge))
+  n_0 = dummy_char(1:1)
+  if( len(TRIM(ADJUSTL(edge))) == 2 ) then
+    l_0 = dummy_char(2:2)
+    two_edges = .false.
+  else
+    l_0 = dummy_char(2:3)
+    two_edges = .true.
+  end if
+ 
+  select case (n_0)
+    case('K')
+      nl_init(1) = 1
+    case('L')
+      nl_init(1) = 2
+    case('M')
+      nl_init(1) = 3
+    case('N')
+      nl_init(1) = 4
+    case default
+      write(stdout,*) 'Needs to be extended'
+  end select
+
+   select case (l_0)
+    case('1')
+      nl_init(2) = 0
+      n_lanczos = 1
+    case('2')
+      nl_init(2) = 1
+      n_lanczos = 2    ! the manifold
+    case('3')
+      nl_init(2) = 1
+      n_lanczos = 4
+    case('4')
+      nl_init(2) = 2
+      n_lanczos = 4
+    case('5')
+      nl_init(2) = 2
+      n_lanczos = 6
+    case('6')
+      nl_init(2) = 3
+      n_lanczos = 6
+    case('7')
+      nl_init(2) = 3
+      n_lanczos = 6
+    case('23')
+      nl_init(2) = 1
+      n_lanczos = 6
+    case('45')
+      nl_init(2) = 2
+      n_lanczos = 10
+    case('67')
+      nl_init(2) = 3
+      n_lanczos = 14
+    case default
+      write(stdout,*) 'Needs to be extended'
+  end select
+
+
+end subroutine select_nl_init