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Interesting (Floating Point) Math Articles



#3

Hi all.

Following a link I found on the December 2007 HHC Calendar page I got to the webpage by prof. William Kahan's.

I found some possibly interesting papers - for example one about floating-point standard.

Maybe that was known stuff, but if not, I hope you'll find it interesting.

Best regards.

Giancarlo


#4

You won't believe this, but I was looking this page just today and thinking if it was to be put into this Forum as a link: It seems you have nothing of my indecision.

Thanks for this.

-- Antonio

#5

Very interesting.

Kahan's paper entitled "Mathematics Written in Sand", which is linked on his webpage, makes reference to several HP calculators.

http://http.cs.berkeley.edu/~wkahan/MathSand.pdf

#6

I'm sure you're all aware of this, but just in case you aren't, Prof. Kahan was the author of the Solve and Integrate routines in the HP-34c, -15c, and 41c Advantage Pac. There are also articles in HP Journal issues by him on these two features.

Stefan


#7

Quote:
There are also articles in HP Journal issues by him on these two features.


Personal Calculator Has Key to Solve Any Equation fx)=0

Handheld Calculator Evaluates Integrals


#8

I read them and I found them VERY interesting. Also the article on May 1983 review about the HP-15C.

Wow! Those times!

-- Antonio


#9

As an add-on, I could see that the Wikipedia topic about IEEE 754 standard is quite interesting and comprehensible (I was able to read and understand almost all of it :-)

By the way, as far as I was able to understand, the HP-71B was the first calculator to fully implement the above standard - but afterwards, did it became the "default" for HP calcs or there were models/families implementing it and others not?

I must confess I'm quite confused and illiterate :-( about the subject.

Thanks in advance to those who will be willing to summarize some piece of information.

Best regards.

Giancarlo


#10

Quote:
As an add-on, I could see that the Wikipedia topic about IEEE 754 standard is quite interesting and comprehensible (I was able to read and understand almost all of it :-)

By the way, as far as I was able to understand, the HP-71B was the first calculator to fully implement the above standard - but afterwards, did it became the "default" for HP calcs or there were models/families implementing it and others not?

I must confess I'm quite confused and illiterate :-( about the subject.

Thanks in advance to those who will be willing to summarize some piece of information.

Best regards.

Giancarlo

I once looked at the code in the HP48 and it appears that most of the IEEE capability was transferred to the HP48, but they don't use some of it. For example, the code to handle NAN's is there, but they don't use it. Also, the different rounding modes aren't used either. Too bad.

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