AFAICT system 360 machines had BCD in microcode, just like any other basic datatype. Z is only the renamed survivor of 360/xx and 370/xxx "boxes".
At 14:33 23/10/2015, you wrote: >--- >On Fri, Oct 23, 2015 at 3:08 AM, <bert at qqmail.nl> wrote: > > > Computers don't store values in base-10 fractions when they use > doubles or > > floats; they use base-2 fractions. This causes that your simple base-10 > > fractions can't be stored exactly. > > >???Unless the architecture implements the newest IEEE-754-2008 "decimal >floating point"??? >ref: https://en.wikipedia.org/wiki/Decimal_floating_point > >???I, personally, only know of one such machine. And it is not really >"popular", except with really _huge_ customers: The IBM z series machine. >It can run 5 different OSes: 4 are IBM proprietary the 5th is Linux. This >machine is not Intel compatible, in any way, shape, or form. And it is >super expensive. Which is why it's not "popular". Running Linux, the >largest has 114 cores and SMT for 228 simultaneous "threads", all in a >single "box". OK, it is a _big_ box <grin/>. >https://pbs.twimg.com/media/BP8HYj9CQAA17g3.jpg:medium That's about the >size on an entire 19 inch rack (more or less). > >Also, as Mr. Long indicated, this entire series of machines have a decimal >data type in the hardware (normally called "packed decimal", which "packs" >2 decimal digits per bytes, except for the last byte which reserves the >last nybble for a sign indicator). There are instructions which translate >from binary to/from packed decimal and packed decimal to/from "printable" >decimal (called zoned decimal for historical reasons due to old style >punched cards). > > > > > > > This is also why those other -not lite- engines have a decimal type, > > processed using much slower integer logic coded in their engines... but > > this doesn't make the current floating point arithmetic broken in > any way. > > > Bert > >-- > >Schrodinger's backup: The condition of any backup is unknown until a >restore is attempted. > >Yoda of Borg, we are. Futile, resistance is, yes. Assimilated, you >will be. > >He's about as useful as a wax frying pan. > >10 to the 12th power microphones = 1 Megaphone > >Maranatha! <>< >John McKown >_______________________________________________ >sqlite-users mailing list >sqlite-users at mailinglists.sqlite.org >http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users >---
