How to calculate the largest real number in IEEE double and single precision representation.

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William 2013-5-14

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How do you calculate (in your own way) the largest real number in IEEE double and single precision representations wihtout using realmax('single') and realmax('double')? thank you!

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Matt Kindig 2013-5-15

Wikipedia gives a pretty good overview of how to do so in its article:

http://en.wikipedia.org/wiki/IEEE-754#Formats

I happened to have been reading this article just today.

James Tursa 2013-5-15

Using just floating point operations? Or allowing for bit manipulation and type casting?

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Answer 1

Jan 2013-5-15

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编辑：Jan 2013-5-15

Using the bit-patterns defined e.g. here http://docs.oracle.com/cd/E19957-01/806-3568/ncg_math.html and a typecast should be sufficient. Because IEEE754 is a convention, there is nothing wrong with using the bit-patterns defined in this convention directly.

[EDITED] What about pow2(2 - eps, 1023)? Does this reply the correct answer?