Elegant users forum

You can change the name of a column, parameter, or array using sddsconvert: sddsconvert input.sdds output.sdds -rename=column,oldName=newName You can also change many names at once using -editnames, e.g., sddsconvert input.sdds output.sdds -rename=column,*y,%/y/z/ would replace 'y' with 'z' in all c...

Ray, The problem seems to be that you have multiple horizontal correctors between some monitors, which makes the response matrix nearly singular. In the "NoWork" files, there is one less monitor in each plane that is "useable" (i.e., downstream of a corrector). Somehow that makes the matrix bad enou...

In elegant, the monitor readout is the beam position at the end of the element, not the center.

Normally, I use zero-length monitors to avoid confusion.

--Michael

Alexey, This is an interesting result. I think the problem is that for orbit response matrix computation, elegant assumes that the kick delivered by the element occurs at the end of the element. This isn't exactly right, but is usually "good enough." I'll have to think about how to solve this. There...

Serkan, You can simulate this using SBEN or CSBEND elements. However, you'll need to manually compute the arc length for each pass. To elegant, this is just a dipole with very large edge angles: E1=E2=(pi-theta)/2, where theta>0 is the bending angle. If the dipole has significant fringe fields, you ...

Shancai, Attached are some files to demonstrate performing a tune scan to optimize dynamic aperture. The scripts work on linux, but may require modification to work on Windows. Also attached is a plot showing what the result looks like. A word of caution: this analyzes only the dynamic aperture. The...

Shancai, The chromaticity is corrected for each function evaluation. You want this, because you are changing quadrupoles. If the chromaticity isn't corrected each time, you'll almost certainly have a result you can't use (dynamic aperture optimized but wrong chromaticity). If you want to correct the...

Shancai, The lattice layout is symmetric, but the quadrupole strengths are not. To get a symmetric solution, Q1, Q2, and Q3, must have the same strength as Q8, Q7, and Q6, respectively. If you make a new beamline like this: twosec: line=(onesp,-onesp) you'll find it has symmetric lattice functions. ...

Shancai, At APS we use elegant and a genetic optimization script for combined dynamic/momentum aperture optimization. However, it requires a linux cluster, since the individual runs take about 1 hour each. You can also perform driving term minimization to improve dynamic/momentum aperture, although ...

Can you post the files in a different format? I don't have any software that will extract files from a RAR file.

tar and zip formats are more universal.

--Michael