Jan : real world examples of nxcanSAS from facilities needed. Tim suggests everyone putting them on Zenodo to get DOIs Pete - post issues on cansas examples github
Reduced data from multiple detectors ....
- Is this a general problem - Jeff : looking at how to handle this for VSANS - Issue for both raw and reduced : raw easier - How to convert? - AJJ : question is of multiple 2D q-spaces rather than detector spaces. - Tim : multiple physical detectors vs moving detector - AJJ : multiple SASdata entries in a single SASentry - Jan : how to get software to read complex datasets (e.g. lots of mag fields with many detectors) - AJJ : discussion of complexity ... some of the complex analyses will require the users to understand their data. Perhaps plugins in e.g. DPDAK?
- Is there a standard location for motors etc. Not really ... each instrument/facility does it differently. - can we have a standard set of metadata tags for NXcanSAS to support - how about more detailed application definitions?
- Pete - search methods, specify search path. - Adam : SESANS data - should create equivalent of SASData for SESANS data. - Brian : how to include multi-modal data - probably at the same level as a SASentry - Detectors : how do we link detector metadata to the q-spaces derived from them. e.g. multiple detector configurations might be used to give a single Q space. This is true for 1D as well. - Stitching : discussion of stitching. How is it automated.
Discussion of dataset representation in python
- xarray - not fully featured. - scippy (c++ version of xarray for mantid) - reinventing numpy! not what we are looking for here. - DAWN has something - nexpy supports network streaming / reading online rather than having to load whole dataset
Multiple detectors - multiple kinds of detector (Tim)
- e.g. optical camera + x-ray detector working at different frequencies. More frames from one than the other - SAXS + WAXS at DESY - just write two nexus files to avoid the problem. Server issues and I/O - I22 - timeframe generation (one file) + two separate detector files. Acquisition gives you a header nexus file linked to the others. Currently looking at stacking in the right order in data structures - slowest at top. - ESS - all timestamped ... - Pete - timestamping at synchrotrons will be coming. XPCS can use this. - Brian : Visualisation - Time slider bars - showing last collected image.
Metadata for Machine Learning
- Datasets generated by Diamond should be put online (3Tb issue!) - Metadata from sample is required. - XPDF users need the information about the sample. (same for liquids neutron diffraction). - Need to move on from basics (Pete) - don't know what we need to know to feed the machine learning algorithms. - What are the users going to give us? - Very little ... - Use header nexus file with link to raw detector data. Basically digital logbook. - Pete - shouldn't limit metadata for edge cases. Need to have the metadata possible and turn off as needed. - Pete - automated addition of data from proposal/safety form - Brian - adding analyte composition and density etc. - Pete - issue with NXsample : requires chemical formula, not composition. - Some are easy for low throughput. Need an efficient way of entering the information. - Should look at what the MX do. - Needs to be end-to-end. Has to be a benefit to user. - Machine learning : Pete - need some samples with bad metadata to teach algorithm!
- Identify the right location for data sets and upload to Zenodo and/or github.
- Linking of detector metadata to sasdata entries.
- Writing of notes with examples for NXcanSAS usage.
- Build a list of suggested metadata with standard names. Including how to build sample descriptions. Brian P to write a proposal for sample relevant metadata and to circulate to Data Formats group