Survey calculations with permanent misalignments show inconsistent results. #1227
Description
This example shows:
mb: sbend,l=1,angle=pi/2;
mq: quadrupole,l=1,k1=0.0;
ss: sequence, l=10;
mq.1:mq, at=1,dx=0,dy=0.0,dpsi=0.0,dphi=0.3,dtheta=0.0;
mb, at=2;
mq.2:mq, at=3,dx=0.0,dy=0.0,dpsi=0.0,dphi=0.3,dtheta=0.0;
endsequence;
beam;
use,sequence=ss;
survey,file=survey.tfs,perm_align_survey=true;
name l angle s x y z theta phi psi
ss$start.ENT 0 0 0 0 0 0 0 0 0
ss$start.EXI 0 0 0 0 0 0 0 0 0
mq.1.ENT 1 0 0.5 0 0 0.5 0 0.3 0
mq.1.EXI 1 0 1.5 0 0.29552 1.45534 0 0.3 0
mb.ENT 1 1.5708 1.5 0 0 1.5 0 0 0
mb.EXI 1 1.5708 2.5 -0.63662 0 2.13662 -1.5708 0 0
mq.2.ENT 1 0 2.5 -0.63662 0 2.13662 -1.5708 1.80954e-17 0.3
mq.2.EXI 1 0 3.5 -1.63662 1.80954e-17 2.13662 -1.5708 1.80954e-17 0.3
ss$end.ENT 0 0 10 -8.13662 0 2.13662 -1.5708 0 0
ss$end.EXI 0 0 10 -8.13662 0 2.13662 -1.5708 0 0
That the first dphi correctly gives an elevation angle, while the second dphi, transform in dpsi giving a tilt!
The code in this location is:
V_AL = V
W_AL = W
if(is_permalign() .ne. 0) then
VE(1) = node_value('dx ')
VE(2) = node_value('dy ')
VE(3) = node_value('ds ')
V_AL = V_AL + matmul(W_AL,VE)
dphi = node_value('dphi ')
dpsi = node_value('dpsi ')
dtheta = node_value('dtheta ')
call sumtrx(dtheta, dphi, dpsi, we_t)
W_AL = matmul(we_t,W_AL) ! Is this the right way?
endif