frequency map analysis

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Hwang, Ji-Gwang
Posts: 42
Joined: 21 Jan 2010, 02:27

frequency map analysis

Post by Hwang, Ji-Gwang » 23 Mar 2010, 12:22

Dear Michael Borland

Hello. I'm master course student in S.Korea at KNU.
Nowadays I study about frequency map analysis. But Still I don't know about command for FMA, such as &frequency_map.
So, If you have some example about FMA, Please could you attach the file to me?
And I have one more question. How to plot tune shift with resonance lines?
I hear about FMA has bugs in 32 bit computer. Is it fixed?

Sincerely yours

From Hwang Ji-Gwang

michael_borland
Posts: 1959
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
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Re: frequency map analysis

Post by michael_borland » 23 Mar 2010, 12:33

Ji-Gwang,

There is an FMA example in the examples file which you can find here
http://www.aps.anl.gov/Accelerator_Syst ... ml#elegant
Once you download and unpack the file, look in PAR/frequencyMap

To plot the resonance lines, use the program sddsresdiag to generate a resonance diagram in a file.

The FMA bug on 32 bit was fixed several releases ago. If you have the latest release, it is fixed.

--Michael

Hwang, Ji-Gwang
Posts: 42
Joined: 21 Jan 2010, 02:27

Re: frequency map analysis

Post by Hwang, Ji-Gwang » 29 Mar 2010, 20:51

Dear Michael Borland

Hello. I try to run the example in PAR/frequencyMap directory through cygwin using windows mechine.
And I get a some result. But I have more questions.
I don't know why axis of the plot of nux and nuy is fractional values?
I think it means that It represent to fraction value of tune of bare lattce. It is right?

And I want to make more small squares or dot in polt.
Actually I change the command "sacle=3->scale=1" in the track file.
So, I get more small squares. but, It is not sufficient to me.
Could you tell me more hints?

From Hwang, Ji-Gwang
Attachments
mpl.png
mpl.png (6.63 KiB) Viewed 14470 times

michael_borland
Posts: 1959
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
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Re: frequency map analysis

Post by michael_borland » 30 Mar 2010, 08:37

Ji-Gwang,

FMA, like FFT, can only determine the fractional part of the tune. Try this:

sddsresdiag resdiag.sdds

sddsplot -col=nux,nuy parTrack.fma -graph=dot,vary -order=spect -split=col=x -col=nux,nuy resdiag.sdds -sever

This will plot the tunes color-coded by initial x amplitude along with a resonance diagram.

--Michael

Hwang, Ji-Gwang
Posts: 42
Joined: 21 Jan 2010, 02:27

Re: frequency map analysis

Post by Hwang, Ji-Gwang » 30 Mar 2010, 09:01

Dear Michael Borland

Thank you for your kind reply. Your reply is very helpful for me.
I get the some result. So, I attached it.
But, I still have one question.

In the figure of result, One point aroud nux=0.9, nuy=0.3 is very far from order points.
I don't know that what means of this point?

I attached other result of FMA get from PLS. This figure look like strange at near the nux=0 and nux=1.
It is right result?

From Hwang, Ji-Gwang
Attachments
mpl.png
mpl.png
mpl.png (11.72 KiB) Viewed 14457 times

michael_borland
Posts: 1959
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

Re: frequency map analysis

Post by michael_borland » 01 Apr 2010, 12:47

Ji-Gwang,

The particle with strange tune values is probably near a coupling resonance. If the x and y motion is strongly coupled, it can be difficult for the algorithm to find both tunes. It looks like the x tune got misidentified in that case.

Your results for PLS show a lot of tune shift with amplitude. The clumping around the 0 and 1 tune lines is probably from particles that are nearly unstable. By the way, I think you need the -order=spect option on your plots to get proper color-coding.

To say more I'd have to see your lattice file.

--Michael

Hwang, Ji-Gwang
Posts: 42
Joined: 21 Jan 2010, 02:27

Re: frequency map analysis

Post by Hwang, Ji-Gwang » 06 Apr 2010, 22:22

Dear Michael Borland

Hello, Sorry to late reply. I attached the lattice file for FMA.
I simualte FMA under 1000 particle and 2000 turns.
Sincerely yours.

From Hwang, Ji-Gwang
Attachments
pls22.lte
(2.1 KiB) Downloaded 837 times

Kahraman
Posts: 2
Joined: 10 Dec 2020, 08:33

Re: frequency map analysis

Post by Kahraman » 11 Dec 2020, 08:11

Hi everyone,

1- Is there a solution for resdiag to plot n-superperiodicity?

Example: My work has a 10 superperiodicity and tunes are nux=27.25, nuy=12.15.

After run, I got a plot like an attachment file. I read an information that is "The coordinate values are between 0 and 1. The defaults are [0.15, 0.9]x[0.15, 0.9]. in sddsplot manual for controlling the plotting region."

2- What is the main difference between &frequency_map and &tune_footprint?

Best regards,
Kahraman.
Attachments
tune_diagram_1.jpg

michael_borland
Posts: 1959
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
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Re: frequency map analysis

Post by michael_borland » 11 Jan 2021, 10:44

Kahraman,

You can use the -superperiodicity option on sddsresdiag to make the appropriate resonance diagram.

The main reasons to use tune_footprint instead of frequency_map are
1. You want to perform optimization of the tune_footprint. You can do this using the quantities described in the manual.
2. You want a simple tune-vs-momentum scan.

--Michael

Kahraman
Posts: 2
Joined: 10 Dec 2020, 08:33

Re: frequency map analysis

Post by Kahraman » 15 Jan 2021, 06:00

Dear Michael,

First of all, thanks a lot for your reply.

I recognized the relation between &frequency_map and &tune_footprint. I figured out it, well. But I have a question to get more clear related with the calculation of the frequency_map. What is the background of it? I guess it runs for n-superperiodicity (full ring), doesn't it?

I am not sure because the plotting of the results of the .fma and .res files is, as if it is one superperiodicity in tune diagram. Even though we simulate it for n-superperiodicity, the resonances which are in one superperiodicity condition are still shown in graphics. See an example a few 4 th order resonances in attach file. Actually, we can see that these resonances are not effective for this example.

Best regards,

Kahraman.
Attachments
4. Order Resonance_Elegant.jpg

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