Re: HP y^x Bug? Message #5 Posted by Dave Hicks on 8 Feb 2002, 3:32 p.m., in response to message #1 by Eric Evans
When HP calculators first appeared, most science and engineering calculations where done on slide rules which yielded 3-4 digits if you were careful. The early calculators were mostly bought by people who were used to these limits. Besides most real-world measurements that they use in their calculations don't exceed 2 to 4 digits of precision anyway, and scientists understand the concept of significant digits.
I think the drive to more accuracy came mostly when calculators became cheap enough for students. Then calculators became less of an engineering tool and more of a pure math tool and many of the owners got calculators before learning about significant digits and also before learning that floating point numbers are approximations. This lead to improved accuracy and also to the "trick" of calculating more digits than you will allow the user to see. (If the user doesn't like or understand the approximate nature of floating point - hide it.)
By the way, back when "The Pentium Bug" was all the rage, someone reported finding "The Pentium Bug" in the HP-48. He did 1 divided by 3 times 3 and got (gasp!) .999999999999 instead of 1.
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