Fix last version of track_a_bend.

bmad-sim · Oct 30, 2023 · 466bbd2 · 466bbd2
1 parent 3bc02fe
commit 466bbd2
Show file tree

Hide file tree

Showing 5 changed files with 15 additions and 10 deletions.
diff --git a/bmad-doc/other_manuals/long_term_tracking.pdf b/bmad-doc/other_manuals/long_term_tracking.pdf
diff --git a/bmad/low_level/symp_lie_bmad.f90 b/bmad/low_level/symp_lie_bmad.f90
@@ -142,9 +142,9 @@ subroutine symp_lie_bmad (ele, param, orbit, track, mat6, make_matrix, offset_el
 ! select the element
 
 key = ele%key
-if (associated(ele%cartesian_map)) key = wiggler$
+if (associated(ele%cartesian_map) .and. ele%field_calc == fieldmap$) key = wiggler$
 
-select case (ele%key)
+select case (key)
 
 !------------------------------------------------------------------
 ! Wiggler
@@ -365,8 +365,8 @@ subroutine symp_lie_bmad (ele, param, orbit, track, mat6, make_matrix, offset_el
 
 case default
 
-  call out_io (s_fatal$, r_name, 'TRACKING NOT YET IMPLEMENTED FOR: ' // key_name(ele%key), &
-                                 'FOR ELEMENT: ', ele%name)
+  call out_io (s_fatal$, r_name, 'TRACKING NOT YET IMPLEMENTED FOR ELEMENT OF TYPE: ' // key_name(ele%key), &
+                                 'FOR ELEMENT: ' // ele%name)
 
 end select
 

diff --git a/bmad/low_level/track_a_bend.f90 b/bmad/low_level/track_a_bend.f90
@@ -345,17 +345,20 @@ subroutine apply_multipole_kicks (coef, step_len, r_step, ix_mag_max, an, bn, ix
 real(rp) an(0:n_pole_maxx), bn(0:n_pole_maxx), an_elec(0:n_pole_maxx), bn_elec(0:n_pole_maxx)
 
 integer i, charge, ix_mag_max, ix_elec_max
+logical exact
 
 ! Calculate field
 
 charge = charge_of(orbit%species)
 
 if (nint(ele%value(exact_multipoles$)) /= off$ .and. ele%value(g$) /= 0) then
+  exact = .true.
   call bend_exact_multipole_field (ele, param, orbit, .true., field, make_matrix)
 
 else
+  exact = .false.
   field = em_field_struct()
-  f_p0c = r_step * ele%value(p0c$) / (step_len * c_light * charge_of(param%particle))
+  f_p0c = r_step * ele%value(p0c$) / (c_light * charge_of(param%particle))
 
   do i = 0, ix_mag_max
     if (an(i) == 0 .and. bn(i) == 0) cycle
@@ -389,12 +392,14 @@ subroutine apply_multipole_kicks (coef, step_len, r_step, ix_mag_max, an, bn, ix
 
 if (ix_mag_max > -1) then
   orb0 = orbit
-  f_coef = step_len * coef * c_dir * (1 + ele%value(g$) * orbit%vec(1)) * c_light / orb0%p0c
+  f_coef = coef * c_dir * (1 + ele%value(g$) * orbit%vec(1)) * c_light / orb0%p0c
+  if (exact) f_coef = f_coef * step_len
   orbit%vec(2) = orbit%vec(2) - f_coef * field%B(2)
   orbit%vec(4) = orbit%vec(4) + f_coef * field%B(1)
 
   if (logic_option(.false., make_matrix)) then
-    df_coef_dx = step_len * coef * c_dir * ele%value(g$) * c_light / orb0%p0c
+    df_coef_dx = coef * c_dir * ele%value(g$) * c_light / orb0%p0c
+    if (exact) df_coef_dx = f_coef * step_len
 
     mat6(2,:) = mat6(2,:) - (f_coef * field%dB(2,1) + df_coef_dx * field%B(2)) * mat6(1,:) - & 
                             (f_coef * field%dB(2,2)) * mat6(3,:)

diff --git a/bsim/long_term_tracking/doc/long_term_tracking.tex b/bsim/long_term_tracking/doc/long_term_tracking.tex
@@ -85,7 +85,7 @@
 
 \title{Long Term Tracking Program}
 \author{}
-\date{David Sagan \\ July 10, 2023}
+\date{David Sagan \\ October 30, 2023}
 
 \begin{document}
 \pdfbookmark[1]{Contents}{contents}
@@ -433,7 +433,7 @@
 To simulate noise, use the \vn{ran()} or \vn{ran_gauss()} functions in a slave expression. Example:
 \begin{code}
   quake: ramper = \{*[y_offset]: 1e-5*ran_gauss()\}, var = \{\}
-\end
+\end{code}
 In this case no ramper variable is needed. 
 When a bunch passes through an element, the slave expression \vn{1e-5*ran_gauss()} is evaluated just
 once. That is, it is assumed that the frequency spectrum of the noise falls below 1/\vn{dt_bunch}

diff --git a/tao/version/tao_version_mod.f90 b/tao/version/tao_version_mod.f90
@@ -6,5 +6,5 @@
 !-
 
 module tao_version_mod
-character(*), parameter :: tao_version_date = "2023/10/29 01:05:04"
+character(*), parameter :: tao_version_date = "2023/10/29 18:44:34"
 end module