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Unread 23-01-2004, 10:00
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Floating Point Tutorial

Quote:
Originally Posted by Jared Stofflett
Can you give me a tutorial or example where I can learn more about this? ALl i've learned so far for decimal points is floating point data types. APpreciate any info.
Did a Yahoo search and got for "floating point" and got this tutorial web address: http://www.cs.utah.edu/~zachary/isp/applets/FP/FP.html

Most important thing about floating point:
DO NOT use unless absolutely neccessary. Any computation with floating-point data (like floats or doubles) is much slower than the same operation with integers (like chars, ints, and longs).
Floating-point data is different than other data because the number that the data itself represents is not directly stored. Instead, a mantissa, sign, and exponent are stored. This is sort of like scientific notation where you know the exponent which for the base 10 and the multiplier. In floating-point, you store every number as:
[sign] [mantissa] x 2 ^ ([exponent])
The 2 is not stored because it is the same for every number. Sign is 0 if the number is positive, and 1 if the number is negative (only one bit stored). Exponents must account for both negative and positive exponents, hence the exponent has a bias. This means that a positive number is added to all exponents in order to make every possible exponent positive.


Hope this helps!