Excel 2007 Arithmetic

[James Silverton]

Hello, All!

According to http://www.msnbc.msn.com/id/21033161/
it looks like Excel is having trouble either displaying or using
2^16. I'd really like to see the sloppy code that causes this!


James Silverton
Potomac, Maryland

E-mail, with obvious alterations:
not.jim.silverton.at.verizon.not

 

[Jim Cone]

And apparently discovered / reported by a " Molham Serry" in the
Public.Excel group on the 22nd.
http://tinyurl.com/338gjd (146 messages)
--
Jim Cone
San Francisco, USA
http://www.realezsites.com/bus/primitivesoftware
(Excel Add-ins / Excel Programming)



"James Silverton"
wrote in message
Hello, All!
According to http://www.msnbc.msn.com/id/21033161/
it looks like Excel is having trouble either displaying or using
2^16. I'd really like to see the sloppy code that causes this!
James Silverton
Potomac, Maryland
E-mail, with obvious alterations:
not.jim.silverton.at.verizon.not

 

[James Silverton]

Jim wrote on Fri, 28 Sep 2007 15:38:51 -0700:


JC> And apparently discovered / reported by a " Molham Serry"
JC> in the Public.Excel group on the 22nd.
JC> http://tinyurl.com/338gjd (146 messages)
JC> --
JC> Jim Cone

I wasn't implying that I had discovered anything about the
binary representation except to wonder if it might be some sort
of overflow problem and a prime example of warning programmers
"If it ain't broke don't fix it".


James Silverton
Potomac, Maryland

E-mail, with obvious alterations:
not.jim.silverton.at.verizon.not

 

[Jon Peltier]

Perhaps it was "fixed" to allow multi-threaded calculations, or to improve
performance of calculations in the new large grid. I don't think MS has the
resources to rewrite code for the sake of rewriting code.

- Jon

 

[iliace]

Let's have a contest to see who can write the best algorithm to parse
the arithmetic with up to 64 levels of function nesting from a text
string. You first. We'll post it up on some OpenSource discussion
board for them to decide how sloppy it is.

 

[Marcus Schöneborn]

Let's have a contest to see who can write the best algorithm to parse
the arithmetic with up to 64 levels of function nesting from a text
string. You first. We'll post it up on some OpenSource discussion
board for them to decide how sloppy it is.

I doubt anyone will be able to replicate the bug... becaust it is not
caused by a sloppy parser or a sloppy calculation engine, but by a buggy
threshold value in some data representation decision that is primarily
done to save memory. So perhaps some == check was done with an epsilon
that should have been an exact ==.

Maybe reading the OOXML specs could give a hint about this
(specifically, reading how Excel stores numbers in files), but I don't
think so (I just expect OOXML to store numbers as text). The specs of
the binary XLS formats could more likely give it away, but these are not
public.