The OPAL Discussion Forum

[Chris Rogers <chris.rogers AT stfc.ac.uk>]

Hi Huiwen,
This error turns up when OPAL can't turn the field map into a regular 
grid. It can occur, for example, because of rounding errors when 
converting to a polar coordinate system (so the grid spacing looks 
irregular).

Could you please send me a copy of the field map file if it isn't too 
big (or put in on a drop box/equivalent if it is huge).

In case you didn't spot it, I would also like to draw your attention to 
the SBEND3D-based example lattice here:

https://gitlab.psi.ch/OPAL/src/wikis/FFA#tracking-through-an-3d-field-map

Regards,
Chris

On 02/01/2019 08:20, Adelmann Andreas (PSI) wrote:
> to me this looks like a unit problem. what are the units of your
> field map?
>
> cheers A
>
> ------
> Dr. sc. math. Andreas (Andy) Adelmann
> Head a.i. Labor for Scientific Computing and Modelling
> Paul Scherrer Institut OHSA/D17 CH-5232 Villigen PSI
> Phone Office: xx41 56 310 42 33 Fax: xx41 56 310 31 91
> Phone Home: xx41 62 891 91 44
> -------------------------------------------------------
> Friday: ETH HPK G 28   +41 44 633 3076
> ============================================
> The more exotic, the more abstract the knowledge,
> the more profound will be its consequences.
> Leon Lederman
> ============================================
>
> On 2 Jan 2019, at 04:10, Huiwen Koay 
> <koay AT rcnp.osaka-u.ac.jp<mailto:koay AT rcnp.osaka-u.ac.jp>> wrote:
>
> Dear Andreas,
>
> This is the error appeared in my shell.
> <image.png>
>
> Thank you again.
>
> Best regards,
> Huiwen
>
>
> On Wed, Jan 2, 2019 at 5:41 AM Adelmann Andreas (PSI) 
> <andreas.adelmann AT psi.ch<mailto:andreas.adelmann AT psi.ch>> wrote:
> Hi Huiwen please add also the std-output so we see how OPAL
> read your field map file.
>
> Thanks Andreas
> ------
> Dr. sc. math. Andreas (Andy) Adelmann
> Head a.i. Labor for Scientific Computing and Modelling
> Paul Scherrer Institut OHSA/D17 CH-5232 Villigen PSI
> Phone Office: xx41 56 310 42 33 Fax: xx41 56 310 31 91
> Phone Home: xx41 62 891 91 44
> -------------------------------------------------------
> Friday: ETH HPK G 28   +41 44 633 3076
> ============================================
> The more exotic, the more abstract the knowledge,
> the more profound will be its consequences.
> Leon Lederman
> ============================================
>
> On 31 Dec 2018, at 09:48, Snuverink Jochem (PSI) 
> <jochem.snuverink AT psi.ch<mailto:jochem.snuverink AT psi.ch>> wrote:
>
> Hi Huiwen,
>
> I am forwarding your question to the OPAL mailing list. Can you add your 
> input file?
>
> Best regards,
> Jochem
>
> Begin forwarded message:
>
> From: Huiwen Koay <koay AT rcnp.osaka-u.ac.jp<mailto:koay AT rcnp.osaka-u.ac.jp>>
> Subject: Fieldmap error using OPAL-CYCL
> Date: 30 December 2018 14:07:24 CET
> To: <jochem.snuverink AT psi.ch<mailto:jochem.snuverink AT psi.ch>>
>
> Dear  Jochem Snuverink,
>
> Hi.
> I am a new phd in beam physics trying to use OPAL for my AVF-cyclotron design.
> I did my magnetic field study using OPERA3D, and would like to investigate 
> the AEO and tune results. However, when I try to execute the input with 
> parameters set using ringdefinition and sbend3d to read in the fmap file, I 
> received error message as follow:
>
> Error> *** User error detected by function 
> "SectorMagneticFieldMap::IO::getInterpolator"
> Error>     Ran out of field points during read operation; check bounds and 
> ordering
>
> It seems like the data size expected from the TOSCA file is different from 
> the real input. According to the manual, we do not have to input anything 
> else than the length and flux unit, so I thought the grid size of the input 
> is defined as given by the header of the tosca output file. However, my 
> prediction seem to be wrong.
>
> Although I can convert the fmap format into other type, but this is the most 
> convenient way. I would greatly appreciate if you have any suggestions to 
> solve this problem.
>
> Your soon reply is greatly appreciated.
> Thank you very much.
>
> Best regards,
> Huiwen


--
ISIS Intense Beams Group

tel: +44 (0)1235 44 6983

Building R2,
Rutherford Appleton Laboratory,
Harwell Science and Innovation Campus,
Didcot.
OX11 0QX