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"{ Encoding: utf8 }"
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5374
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"
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COPYRIGHT (c) 2018 by eXept Software AG
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All Rights Reserved
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This software is furnished under a license and may be used
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only in accordance with the terms of that license and with the
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inclusion of the above copyright notice. This software may not
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be provided or otherwise made available to, or used by, any
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other person. No title to or ownership of the software is
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hereby transferred.
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"
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"{ Package: 'stx:libbasic2' }"
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"{ NameSpace: Smalltalk }"
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LimitedPrecisionReal variableByteSubclass:#HalfFloat
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instanceVariableNames:''
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classVariableNames:''
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poolDictionaries:''
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category:'Magnitude-Numbers'
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!
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!HalfFloat class methodsFor:'documentation'!
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copyright
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"
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COPYRIGHT (c) 2018 by eXept Software AG
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All Rights Reserved
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This software is furnished under a license and may be used
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only in accordance with the terms of that license and with the
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inclusion of the above copyright notice. This software may not
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be provided or otherwise made available to, or used by, any
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other person. No title to or ownership of the software is
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hereby transferred.
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"
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!
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documentation
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"
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HalfFloats represent rational numbers with very very limited precision.
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There are no instances of it to be created - halfFloats are only possibly stored
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inside instancs of HalfFloatArray, which are presented as floats or shortFloats when accessd.
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However, this class is provided for queries about precision, bits in mantissa etc.
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Representation:
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16bit single precision IEEE floats
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10 bit fraction + 1 hidden bit, providing a precision of 11bits,
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5 bit exponent,
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6 decimal digits (approx.)
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Range and Precision of Storage Formats: see LimitedPrecisionReal >> documentation
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[author:]
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Claus Gittinger
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[see also:]
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Number
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Float LongFloat Fraction FixedPoint Integer Complex
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HalfFloatArray FloatArray DoubleArray
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"
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! !
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!HalfFloat class methodsFor:'queries'!
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eBias
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"Answer the exponent's bias;
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that is the offset of the zero exponent when stored"
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^ 15
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!
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emax
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^ 15
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!
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emin
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^ -14
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!
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numBitsInExponent
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"answer the number of bits in the exponent
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This is an IEEE float, where 4 bits are available:
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seeeemmm mmmmmmmm
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"
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^ 4
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!
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numBitsInMantissa
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"answer the number of bits in the mantissa (the significant).
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This is an IEEE binary16, where 11 bits are available (the hidden bit is not counted here):
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seeeemmm mmmmmmmm
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"
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^ 11
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!
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radix
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"answer the radix of a Float's exponent
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This is an IEEE float, which is represented as binary"
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^ 2
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! !
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!HalfFloat class methodsFor:'documentation'!
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version_CVS
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^ '$Header$'
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! !
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