Hi Jonathan, We discussed about VAX floats last November:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1811&L=CCP4BB&O=D&P=63307 https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1811&L=CCP4BB&O=D&P=65015 https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1811&L=CCP4BB&O=D&P=65531 In short, the factor of 4 comes from: a) a bias of 128 instead of 127, b) a different convention in the scientific notation. Would you be so kind as to send me a specimen of the VAX LCF file off-list? I am also quite interested in archaeology. Zhijie ________________________________ From: CCP4 bulletin board <[email protected]> on behalf of Jonathan Cooper <[email protected]> Sent: Saturday, July 13, 2019 4:21 PM To: [email protected] Subject: [ccp4bb] More LCF archaeology (unit cell parameters this time). I am trying to use a hex editor to read the unit cell parameters from the headers of 80's VAX LCF files and I can definitely find them in front of the column labels as six regularly spaced 32-bit floats. However, they seem to be multiplied by a factor of 4 and the final corrected values of a, b, c, alpha, beta and gamma are a bit more approximate than I would expect. I can't work out what's going on from the fortran yet so any clues would be much appreciated. ________________________________ 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
