>> ah, nostalgia Ah, "mantissa!" Haven't heard "mantissa" in decades...
Is there such a thing as a "praying mantissa?" Seems like there could be a good geek joke about it. JPK > However all procedures I have seen use a division of 4, which is quite > puzzling to me. A real data file containing meaningful numbers (eg., HKL > indices) would be very helpful. Thanks in advance. > > Zhijie > > > On Nov 13, 2018, at 2:21 PM, Johan Hattne <hat...@ucla.edu> wrote: > > > > Related by not exactly on topic: would anybody on the list be able to share > > old map files (not MTZ:s) with Convex, Cray, Fujitsu, or VAX reals/strings? > > I’d be interested to see what those files actually look(ed) like. > > > > // Best wishes; Johan > > > >> On Nov 9, 2018, at 18:38, Zhijie Li <zhijie...@utoronto.ca> wrote: > >> > >> Hi all, > >> > >> On linux there are a few good GUI HEX editors. Here I’d like to > >> recommend BLESS, which conveniently displays all possible numerical > >> interpretations of the four bytes under cursor. It also allows the > >> user to switch between big endian or little endian through a > >> checkbox. Unfortunately all floats are assumed to be IEEE754, > >> therefore VAX floats won’t be interpreted correctly. ( The > >> simplest way to convert vax to ieee float would be to write a > >> little program to do some bit operations. I’d be happy to take that > >> as my weekend project) > >> > >> > >> BTW, along the line of space efficiency, I can’t help noticing that the > >> miller indices are saved as float32 in mtz, as all other numbers in mtz. > >> This certainly have made mtz format a beautiful homogeneous data format > >> ;). In this particular case, if we have doubts about the reliability of > >> the machine stamp, trying to restore the miller indices would be a good > >> way to test hypotheses. > >> > >> Zhijie > >> > >>> On Nov 9, 2018, at 9:04 PM, James Holton > >>> <0000270165b9f4cf-dmarc-requ...@jiscmail.ac.uk> wrote: > >>> > >>> As a beamline scientist I must say I am glad that diffraction image data > >>> is not usually stored as ASCII text. In fact, I am slowly warming to the > >>> idea of storing it as not just binary, but compressed formats. Problem, > >>> I'm sure will be that it won't be long before we forget how to > >>> decompress them, as most of the algorithms we are using aren't all that > >>> widespread. Probably around the same time future generations will curse > >>> us for using ASCII instead of unicode, which is a 16-bit standard. I'm > >>> sure we will be reviled for limiting ourselves so, just to save a factor > >>> of two in disk space. > >>> In situations like this I always use the unix "od" command. It makes > >>> everything "human readable" by converting the bytes into strings you can > >>> read. Then it is just a matter of figuring out what the bytes are. > >>> Unfortunately, "od" only decodes floats on the native platform, so if the > >>> mtz is from another platform (Windows vs Linux, for example), then you > >>> might need to do some swapping. Thus far, I have encountered files that > >>> require one of a few swapping strategies in order to make them work: > >>> > >>> 1 2 3 4 - no swapping > >>> > >>> 4 3 2 1 - reverse all bytes > >>> > >>> 3 4 1 2 - swap words and swap bytes within the words > >>> 2 1 4 3 - reverse of previous > >>> > >>> 2-1 1 4 3 - same as last, but if not all zero, decrement byte #2 > >>> before swapping > >>> 3 4 1 2+1 - same as 3412, but if not all zero increment byte #2 > >>> before swapping I'm sure there are other combinations, but the oldest MTZ > >>> I have is only from 1996. > >>> > >>> -James Holton > >>> MAD Scientist > >>> > >>> > >>>> On 11/9/2018 4:47 AM, Eleanor Dodson wrote: > >>>> Anyone any idea what to do about this?? Created in 1992!! > >>>> Seems unreadable.. > >>>> > >>>> No CTYP lines input for file: 1 > >>>> Indices output even if all data items flagged "missing" > >>>> Warning, NOT all LABOUT data lines given > >>>> Warning: Machine stamp corrupted? Assuming native format. > >>>>>>>>>> CCP4 library signal library_file:End of File (Error) > >>>> > >>>> > >>>> To unsubscribe from the CCP4BB list, click the following link: > >>>> https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > >>>> > >>> > >>> > >>> To unsubscribe from the CCP4BB list, click the following link: > >>> https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > >>> > >> > >> To unsubscribe from the CCP4BB list, click the following link: > >> https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > >> > > > > Research Specialist @ Gonen Lab > > ____________________________________________________ > > UCLA * 615 Charles E. Young Drive South > > BSRB #347 * Los Angeles, CA 90095 > > > > #################################################################### > > #### > > > > To unsubscribe from the CCP4BB list, click the following link: > > https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > > ###################################################################### > ## > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > -- Ethan A Merritt Biomolecular Structure Center, K-428 Health Sciences Bldg MS 357742, University of Washington, Seattle 98195-7742 ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
