Search found 1459 matches

by michael_borland
20 Nov 2019, 16:55
Forum: General
Topic: Different simulation time in two systems
Replies: 4
Views: 20

Re: Different simulation time in two systems

For the parallel version, better performance is often obtained by modifying the MPI IO parameters. E.g., try putting this command at the top of the .ele file:

Code: Select all

&global_settings
        mpi_io_read_buffer_size = 400000,
        mpi_io_write_buffer_size = 400000,
&end
--Michael
by michael_borland
20 Nov 2019, 16:52
Forum: Ring Tracking
Topic: how to model overlapping corrector magnets and focusing elements
Replies: 2
Views: 20

Re: how to model overlapping corrector magnets and focusing elements

Gregg, The best way to combine quadrupoles with steering is to use the HKICK and VKICK parameters on the KQUAD element. There's no limit to how high the multipole components can be. Using ETILT by itself shouldn't result in accuracy issues. The effects on the trajectory are computed with some analyt...
by michael_borland
20 Nov 2019, 16:43
Forum: Feature Requests
Topic: Gaussian beam initialization with moments_output results
Replies: 3
Views: 3848

Re: Gaussian beam initialization with moments_output results

Zhe,

This bug will be fixed in the next release.

Thanks for letting me know.

--Michael
by michael_borland
20 Nov 2019, 16:10
Forum: General
Topic: plotting phase space separately in each pass
Replies: 1
Views: 47

Re: plotting phase space separately in each pass

Gunn, Each pass of the beam is put into a separate "page" in the output file. By default, sddsplot treats all the pages as a single set of data. Plot all the data together: sddsplot W1.sdds -col=t,p -graph=dot Split the data pages, but plot the data together with different color: sddsplot W1.sdds -c...
by michael_borland
20 Nov 2019, 16:01
Forum: Ring Tracking
Topic: Output from frequency_map doesn't agree with tracking
Replies: 1
Views: 58

Re: Output from frequency_map doesn't agree with tracking

Teresia,

The most common cause of this would be using too few kicks on the CSBEND and KQUAD elements. This can cause tune errors, but also path-length errors (due to CSBEND). Try increasing the N_KICKS parameters.

--Michael
by michael_borland
04 Nov 2019, 15:01
Forum: Ring Tracking
Topic: Study on coupled bunch Instability in ultra-low emittance ring
Replies: 1
Views: 25

Re: Study on coupled bunch Instability in ultra-low emittance ring

Pradeep, The procedure should be very similar to the 48-bunch example, just changing 48 to 1536 in various places. There is no meaningful limit on the number of bunches, beyond memory limitations related to the total number of particles. The number of particles need not be that large if you are only...
by michael_borland
29 Oct 2019, 11:12
Forum: Linac Tracking
Topic: RFTMEZ0: on-crest phase depending on number of cells or cavity length?
Replies: 2
Views: 41

Re: RFTMEZ0: on-crest phase depending on number of cells or cavity length?

Felix, The issue is that RFTMEZ0 has set up the phasing of the fields before it performs integration. It does this by assuming that the fields reach their peak when the *drifting* particle reaches the center of the element. This results in a ~180-degree phase difference between your 2-cell and 20-ce...
by michael_borland
29 Oct 2019, 09:11
Forum: General
Topic: serial version of elegant renumbers particleID values
Replies: 3
Views: 65

Re: serial version of elegant renumbers particleID values

Gregg, If you need the files sorted by particleID, just use sddssort sddssort -column=particleID <filename> If you then want to read the file as a text file, I recommend using sdds2plaindata to ensure you get consistent ordering of the data columns. This is generally not guaranteed in SDDS files (si...
by michael_borland
28 Oct 2019, 16:05
Forum: Linac Tracking
Topic: Question about elegant to ASTRA conversion
Replies: 2
Views: 50

Re: Question about elegant to ASTRA conversion

Wei Hou, astra2elegant considers the ASTRA fiducial particle to be an ordinary particle, so it appears in the elegant file. When converting back, elegant2astra doesn't "know" that one of the particles is special, but it knows that ASTRA needs a fiducial particle, so it creates one. Hence, you'll add...
by michael_borland
25 Oct 2019, 16:11
Forum: General
Topic: serial version of elegant renumbers particleID values
Replies: 3
Views: 65

Re: serial version of elegant renumbers particleID values

Gregg,

I'm really surprised to hear this, since no version of elegant should renumber the particles. The only exception is the SCRIPT element, which will renumber the particles if USE_PARTICLE_ID=0.

Can you send me an example that illustrates the problem?

--Michael