Do not close and re-open if it is the same file

Inst_eddies/input_ssh.f90

@@ -108,9 +108,12 @@ contains
          new_fill_value = huge(0.))
     ! (We cannot keep the original fill value because Contour_531
     ! works with an upper limit for valid values.)
-    call nf95_close(ncid)
 
-    call nf95_open(uv_fname, nf95_nowrite, ncid)
+    if (uv_fname /= ssh_fname) then
+       call nf95_close(ncid)
+       call nf95_open(uv_fname, nf95_nowrite, ncid)
+    end if
+
     call get_var(periodic, u, ncid, name = "ugos", &
          new_fill_value = ieee_value(0., IEEE_QUIET_NAN))
     call get_var(periodic, v, ncid, name = "vgos", &