FITACF3 status

Jun 21, 2020

The status of the FITACF3.0 package was discussed at the PI meeting on 5 June 2020.

The following decisions were made:

  • Data files generated using FITACF3 will not be distributed to the scientific community
  • FITACF2.5 will continue to be the default fitting algorithm in the RST

The reason for this decision was that the FITACF3 package has not been properly documented, and that it requires additional testing.

Frequently Asked Questions

Which fitting algorithm is better, FITACF2.5 or FITACF3.0?

That depends on who you ask, which radar you’re using, and your definition of “better”!

FITACF3.0 includes several scientifically-sound improvements to the standard SuperDARN fitting algorithm (FITACF2.5). However, the perceived quality of the processed data varies between radars. In particular, for some radars the fit-level data appears to be very noisy when processed with FITACF3.0. This is currently being investigated by the DAWG.

Note that the convection mapping software in RST has not been tested with data processed using FITACF3. It is not clear whether the convection mapping procedure is sensitive to the fitting algorithm used. Current testing efforts are focused on the raw- and fit-level data.

What is the default fitting algorithm in RST? Who makes this decision?

The default fitting algorithm is FITACF2.5. This is decided by the SuperDARN Executive Council (i.e. the Principal Investigators).

FITACF3.0 has never been the default fitting algorithm in RST. It has been included in RST as a non-default option since January 2018 (RST4.1 release).

Can I still use FITACF3 for my own research?

Yes, scientists are free to decide which fitting algorithm to use for their own research.

The DAWG recommends that all users specify which version of RST was used in their published work (using the citable DOI), and list the data processing options used (e.g. -fitacf-version), so that their work is reproducible.

What documentation is available for FITACF3?

The documentation currently available for the FITACF3 package can be found here. Additionally, the FITACF3.0 source code is nicely commented. You are welcome to contact us if you have questions about the package.

The Data Analysis Working Group is leading a renewed effort to test and document FITACF3.0.

How do I obtain SuperDARN data processed with FITACF3?

SuperDARN radar data processed using FITACF3 will not be provided on any of the SuperDARN data servers until further notice. Therefore, you need to process the raw data yourself using RST:

make_fit -fitacf-version 3.0 [file].rawacf > [file].fitacf

How do I determine which version of FITACF was used to process a particular file?

The following code will print the major and minor fitacf revision/version numbers recorded in a fitacf file (requires RST):

dmapdump [file].fitacf | grep fitacf.revision

This will produce one of the following:

# FITACF2.5:
int     "fitacf.revision.major" = 2
int     "fitacf.revision.minor" = 5

# FITACF3.0:
int     "fitacf.revision.major" = 3
int     "fitacf.revision.minor" = 0