[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Reply to: [list | sender only]
Removing the '_array_element_size' category or not ?
- To: imgcif-l@bnl.gov
- Subject: Removing the '_array_element_size' category or not ?
- From: Andy Hammersley <hammersl@esrf.fr>
- Date: Thu, 26 Feb 98 17:33:24 +0100
As I mentioned in the previous e-mail, I'd like to consider putting the '_array_element_size.size' data item into the '_array_structure_list' category. To me this would seem slightly simpler. While on this aspect, I would like to add one more data item, one to define the units of each dimension. This would be an enumerated list of a standard list of possible units e.g. 'metres', 'kilogrammes', 'seconds', 'degrees', 'radians', 'joules', 'keV', 'scans'. As you can see we should presumably have standard SI units, and probably some commonly used alternatives. An alternative would be to use a general term e.g. 'distance', 'weight', 'time', etc., but using the units themselves seems slightly clearer to me. These are basically our n-dimensional axis labels, but by using a standard list they can be automatically processed when appropriate. '_array_structure_list.units' might be an appropriate data name. e.g. # Define dimensionality and element rastering, sizes, and units loop_ _array_structure_list.array_id _array_structure_list.index _array_structure_list.dimension _array_structure_list.precedence _array_structure_list.direction _array_structure_list.size _array_structure_list.units image_1 1 768 1 increasing 100.5e-6 metres image_1 2 512 2 decreasing 99.5e-6 metres image_2 1 1000 1 increasing 0.02 degrees image_2 2 128 2 increasing 50.0 seconds What are other peoples feelings on the category for 'element_size' and 'units' ? (It clear to me that they belong together). Perhaps, in particular, Paul Ellis can make a comment, since he's going to be writing the I/O library software. As presently defined, the equivalent of the above example would be: # Define dimensionality and element rastering loop_ _array_structure_list.array_id _array_structure_list.index _array_structure_list.dimension _array_structure_list.precedence _array_structure_list.direction image_1 1 768 1 increasing image_1 2 512 2 decreasing image_2 1 1000 1 increasing image_2 2 128 2 increasing # Define element sizes, and units loop_ _array_element_size.array_id _array_element_size.index _array_element_size.size _array_element_size.units image_1 1 100.5e-6 metres image_1 2 99.5e-6 metres image_2 1 0.02 degrees image_2 2 50.0 seconds If, I'm the only one who feels that the categories should be combined, then I suggest that we leave them as presently defined, and the 'units' data item joins the '_array_element_size' category. I think once this aspect is decided, we have everything needed to define abstract arrays (and now slightly less abstract owing to the 'units'). Then will come the experiment geometry ... Andy
Reply to: [list | sender only]
- Follow-Ups:
- Re: Removing the '_array_element_size' category or not ? (I. David Brown)
- Prev by Date: imgCIF / CBF Status
- Next by Date: Re: Removing the '_array_element_size' category or not ?
- Prev by thread: AFP/XPLOR/ Electronic Mailing/Transaction Processing Project Manager
- Next by thread: Re: Removing the '_array_element_size' category or not ?
- Index(es):