unres multichain extconf MD chainbuild

diff --git a/source/unres/src_MD-M/readrtns_CSA.F b/source/unres/src_MD-M/readrtns_CSA.F
index 3a4981c..ab7b808 100644 (file)
--- a/source/unres/src_MD-M/readrtns_CSA.F
+++ b/source/unres/src_MD-M/readrtns_CSA.F
@@ -1107,6 +1107,53 @@ C initial geometry.
           omeg(i)=-120d0*deg2rad
           if (itype(i).le.0) omeg(i)=-omeg(i)
          enddo
+c from old chainbuild
+C
+C Define the origin and orientation of the coordinate system and locate the
+C first three CA's and SC(2).
+C
+      call orig_frame
+*
+* Build the alpha-carbon chain.
+*
+      do i=4,nres
+       call locate_next_res(i)
+      enddo     
+C
+C First and last SC must coincide with the corresponding CA.
+C
+      do j=1,3
+       dc(j,nres+1)=0.0D0
+        dc_norm(j,nres+1)=0.0D0
+       dc(j,nres+nres)=0.0D0
+        dc_norm(j,nres+nres)=0.0D0
+        c(j,nres+1)=c(j,1)
+        c(j,nres+nres)=c(j,nres)
+      enddo
+C
+C Define the origin and orientation of the coordinate system and locate the
+C first three CA's and SC(2).
+C
+      call orig_frame
+*
+* Build the alpha-carbon chain.
+*
+      do i=4,nres
+       call locate_next_res(i)
+      enddo     
+C
+C First and last SC must coincide with the corresponding CA.
+C
+      do j=1,3
+       dc(j,nres+1)=0.0D0
+        dc_norm(j,nres+1)=0.0D0
+       dc(j,nres+nres)=0.0D0
+        dc_norm(j,nres+nres)=0.0D0
+        c(j,nres+1)=c(j,1)
+        c(j,nres+nres)=c(j,nres)
+      enddo
+
+c
         else
           if(me.eq.king.or..not.out1file)
      &     write (iout,'(a)') 'Random-generated initial geometry.'