Elegant users forum

Philippe, That is very weird. I don't see a problem with either the serial or the parallel version. I tried it on my linux workstation and Improv, with the latest source and version 2023.4. Are you using Improv? If so, check that you have the right modules loaded: $ module list Currently Loaded Modu...

Wei Hou,

The basic problem is that a stable periodic solution will not always exist for arbitrary values of the cell parameters. You can set the quadrupole K1 values to something quite small (e.g., |K1|=0.001) to make it less likely that the initial conditions are unstable.

--Michael

You can include the drift length as a variable in the optimization and then add an optimization term to make it equal the desired value.

See attached file.

--Michael

Alex, Something is not right in construction of the magnet field map file. For example, if I plot By(x=0,y=0,z) using $ sddsplot -col=z,By magmnew.sdds -filter=col,y,-1e-6,1e-6 -filter=col,x,-1e-6,1e-6 -graph=sym I get plot-x0-y0.png Also, if try to plot By(x,y) as a function of z using $ sddssort m...

As the manual states: "this command is deprecated, because it is too difficult to tune it to get reliable answers. The use of driving term computation in twiss_output is recommended instead, even though it doesn’t include all possibly relevant effects. For tune-spread calculations, the tune_footprin...

I converted small2.csv to SDDS. The range of data is quite small (+/-0.01mm), so there's hardly any room for the beam to move. Also, the grid is only 5x5, so the interpolation may not work well. Your data needs to cover the range of motion of the beam and have sufficient points in each dimension, e....

The problem is that you've specified 19 indices (a 19-dimensional scan!) but only one vary_element command. You need at least one vary_element command per index. For example, &run_control n_indices = 2 &end &vary_element index_number=0, index_limit=11, ... &end &vary_element index_number=1, index_li...

Can you post an example to help me understand what you are trying?

--Michael

I'll have to look into why that term is missing. Meanwhile, you can add "TRACKING_MATRIX=2" to the definition of the KQUAD element to get a tracking-based matrix, which includes this term. I suppose that other R5X and RX6 terms will also change as a result. One thing to be aware of in comparing to o...

Gregg, Unfortunately, that feature is not supported for the parallel version, although you have no way to know that from the manual. Those messages indicate that each processor is trying to open the same file, and failing. I'll put it on my to-do list to provide parallel support, although I wouldn't...