Hello, all,


In the following script, I want to calculate the optics with different skew quadrupole strength settings. Therefore, I used a Do-loop.

I found " cell; cal;" don't refresh the optics parameters in my Do-Loop. However, I found the skew quadrupole strengths have been changed by "setelement" in each iteration.


Someone please help to look at it, thanks.

yun


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READ "./blue_pp_inj.sad";

MASS=938279600;
MOMENTUM=100000000000;
# gama=106.575722;
FSHIFT=0;
FFS USE=RING;

!----tracking parameters, YOU DECIDE THE FOLLOWING INPUTS

cell;
cal;

CELL;
FIT;
NX 28.72;
NY 29.73;
FREE QF, QD;
GO;
SAVE;

cell;
cal;


!-----coupling situation changing


ftwiss=OpenWrite["Twiss_output"];

Do[ {



f1strength= -0.0002+0.00002*k;
f2strength= 0.000;
f3strength= 0.0000;

SetElement["SQSK8" ,, "K1"-> f1strength];
SetElement["SQSK2" ,, "K1"->-1.0*f1strength];
SetElement["SQSK10" ,, "K1"-> f2strength];
SetElement["SQSK4" ,, "K1"->-1.0*f2strength];
SetElement["SQSK6" ,, "K1"-> f3strength];
SetElement["SQSK12" ,, "K1"->-1.0*f3strength];

Print[LINE[{"K1","ROTATE"}, "SQSK8"] ];
Print[LINE[{"K1","ROTATE"}, "SQSK10"] ];
Print[LINE[{"K1","ROTATE"}, "SQSK6"] ];


cell;
cal;

Do[
{

If [ LINE["NAME",j]== "PLLBPM",

......
......

Print["------------------------> k= ",k];
Write[ftwiss, f1strength," ",qx," ",qy," ",r1," ",r2," ",ratio," ",tanang1," ",tanang2];

];

},{j,1, LINE["POSITION", "$$$" ] } ];


},{k,0,20} ];

fclose[ftwiss];

Abort;

Use ``FFS["CELL; CAL;"];'' insted of ``cell; cal;''