On Wed, 14 Aug 2019 11:34:14 -0700, Charles Mills wrote: >... Not to mention that time in microseconds since 1900 would have fit in a >64-bit integer. > With a several thousand year range. And when another choice was made there were many extant birth dates and contract dates prior to 1900. I still feel that ETOD should be made signed to accommodate historic dates.
>Of course, ease of conversion and formatting is/was also a factor. The year >could have been stored in binary, but that might have required conversion from >and to decimal as punched into Hollerith cards and printed on reports. > IBM, more than most other suppliers, was swayed by a desire that the storage format be human-readable. I suspect this was the motive for making packed decimal sign-magnitude rather than 10s-complement which would have provided 5 times the range in the same storage and avoided the need for a recomplement when the result has unexpected sign. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
