The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » sci.math.* » sci.math

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: bcd arithmetic
Replies: 5   Last Post: Jul 5, 1996 7:41 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Tom Watson

Posts: 1
Registered: 12/12/04
Re: bcd arithmetic
Posted: Jun 14, 1996 2:24 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

In article <4pmieo$>, (Gian Carlo
Macchi) wrote:

> In article <>,
> says...

> >...
> >Blah. This is, IMHO, not much more than IBM still trying to justify
> >

> Only for info. When IBM designed PL/I (that *should* become the one
> language), also decimal floating point types were taken into account,
> besides decimal fixed point.
> Decimal fixed point types were implemented on some computers via decimal
> integer arithmetic (e.g. in IBM 370 serie and derived), but as far as I
> know, decimal floating point types were neither implemented based on
> hardware, nor simulated via software, and remained pure "artificial" types.

But there were computers (from an era long long ago!!) that used BCD
floating point, even in hardware. You could get up to 99 digits of
accuracy if you felt like it, but the fortran compiler only went up to 28.

Yes, the IBM 1620 had hardware floating point and it WAS bcd. Yes they
had software to use the same data that the floating point hardware used.

All back in the 60's. You see the 1620 was IBM's first "personal"
computer. You used it up close and very personal. Of course, you ended
up fighting for console time, and trying to debug as fast as possible.
Interesting times...

You're right in one respect. The 360/370... machines don't have BCD
floating point.

Tom Watson (Home:

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.