author | Jan Vrany <jan.vrany@fit.cvut.cz> |
Tue, 11 Oct 2011 16:53:59 +0100 | |
branch | jv |
changeset 17883 | 209190914636 |
parent 17846 | 24edc476ac18 |
child 17892 | d86c8bd5ece3 |
permissions | -rw-r--r-- |
7445 | 1 |
" |
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COPYRIGHT (c) 2003 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:libbasic' }" |
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LimitedPrecisionReal subclass:#LargeFloat |
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instanceVariableNames:'exponent mantissa precision' |
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classVariableNames:'Zero One NaN PositiveInfinity NegativeInfinity Pi_1000 E_1000' |
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poolDictionaries:'' |
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category:'Magnitude-Numbers' |
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! |
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!LargeFloat class methodsFor:'documentation'! |
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copyright |
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" |
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COPYRIGHT (c) 2003 by eXept Software AG |
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All Rights Reserved |
|
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||
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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 |
|
31 |
inclusion of the above copyright notice. This software may not |
|
32 |
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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7547 | 40 |
Experimental Code. |
8634 | 41 |
The implementation is neither complete nor tuned for performance - still being developed. |
7547 | 42 |
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7445 | 43 |
This class provides arbitrary precision floats. These are represented as: |
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exponent, |
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mantissa |
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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 ShortFloat Fraction FixedPoint |
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SmallInteger LargeInteger |
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" |
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! |
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examples |
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" |
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(1 to:1000) inject:1 asLargeFloat into:[:p :m | p * m] |
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(1 to:1000) inject:1 into:[:p :m | p * m] |
7445 | 62 |
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Time millisecondsToRun:[ |
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(1 to:20000) inject:1 asLargeFloat into:[:p :m | p * m] |
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] |
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Time millisecondsToRun:[ |
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(1 to:20000) inject:1 into:[:p :m | p * m] |
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] |
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" |
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! ! |
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!LargeFloat class methodsFor:'instance creation'! |
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fromInteger:anInteger |
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^ self basicNew |
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mantissa:anInteger |
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exponent:0 |
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||
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" |
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LargeFloat fromInteger:123456 |
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1 asLargeFloat |
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2 asLargeFloat |
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1000 factorial asLargeFloat |
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" |
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! |
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fromLimitedPrecisionReal:aLimitedPrecisionReal |
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|shifty numBytes numBitsInMantissa maskMantissa numBitsInExponent maskExponent |
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numIntegerBits numBits biasExponent lpRealClass sign expPart fractionPart fraction exp| |
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aLimitedPrecisionReal isFinite ifFalse:[ |
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aLimitedPrecisionReal isNaN ifTrue:[^ self NaN]. |
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aLimitedPrecisionReal > 0 ifTrue:[^ self infinity]. |
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^ self negativeInfinity |
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]. |
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lpRealClass := aLimitedPrecisionReal class. |
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numBytes := aLimitedPrecisionReal basicSize. |
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numBitsInMantissa := lpRealClass numBitsInMantissa. maskMantissa := (1 bitShift:numBitsInMantissa) - 1. |
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numBitsInExponent := lpRealClass numBitsInExponent. maskExponent := (1 bitShift:numBitsInExponent) - 1. |
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numIntegerBits := lpRealClass numBitsInIntegerPart. |
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numBits := numBitsInMantissa + numBitsInExponent. |
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biasExponent := maskExponent bitShift:-1. |
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106 |
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shifty := LargeInteger basicNew numberOfDigits:numBytes. |
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UninterpretedBytes isBigEndian ifTrue:[ |
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1 to:numBytes do:[:i | shifty digitAt:(numBytes+1-i) put:(aLimitedPrecisionReal basicAt:i)]. |
|
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] ifFalse:[ |
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1 to:numBytes do:[:i | shifty digitAt:i put:(aLimitedPrecisionReal basicAt:i)]. |
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]. |
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sign := (shifty bitAt:numBits+1) == 0 ifTrue: [1] ifFalse: [-1]. |
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expPart := (shifty bitShift:numBitsInMantissa negated) bitAnd: maskExponent. |
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fractionPart := shifty bitAnd:maskMantissa. |
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( expPart=0 and: [ fractionPart=0 ] ) ifTrue: [ ^ self zero ]. |
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numIntegerBits == 0 ifTrue:[ |
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" Replace omitted leading 1 in fraction (Notice: quadIEEE format does not do this)" |
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fraction := fractionPart bitOr: (maskMantissa + 1). |
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] ifFalse:[ |
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fraction := fractionPart. |
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]. |
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"Unbias exponent" |
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exp := biasExponent - expPart + (numBitsInMantissa - numIntegerBits). |
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^ self basicNew |
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mantissa:(fraction * sign) |
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exponent:(exp negated) |
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" |
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1.0 asLargeFloat |
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2.0 asLargeFloat |
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20000.0 asLargeFloat |
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2e6 asLargeFloat |
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1e300 asLargeFloat |
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2e300 asLargeFloat |
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0.5 asLargeFloat |
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0.25 asLargeFloat |
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(1.0/20000.0) asLargeFloat |
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2e-6 asLargeFloat |
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2e-300 asLargeFloat |
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-1.0 asLargeFloat |
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-0.5 asLargeFloat |
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Float NaN asLargeFloat |
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Float infinity asLargeFloat |
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Float negativeInfinity asLargeFloat |
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" |
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! |
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mantissa:m exponent:e |
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^ self basicNew mantissa:m exponent:e |
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" |
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LargeFloat mantissa:1 exponent:0 |
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LargeFloat mantissa:2 exponent:0 |
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LargeFloat mantissa:4 exponent:0 |
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LargeFloat mantissa:8 exponent:0 |
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LargeFloat mantissa:1 exponent:-1 |
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LargeFloat mantissa:1 exponent:-2 |
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LargeFloat mantissa:1 exponent:-3 |
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" |
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! |
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mantissa:m exponent:e precision:p |
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^ self basicNew mantissa:m exponent:e precision:p |
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! ! |
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172 |
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!LargeFloat class methodsFor:'class initialization'! |
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initialize |
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NaN := self mantissa:0 exponent:999. |
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PositiveInfinity := self mantissa:0 exponent:1. |
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NegativeInfinity := self mantissa:0 exponent:-1. |
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One := self mantissa:1 exponent:0. |
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Zero := self mantissa:0 exponent:0. |
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" |
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LargeFloat initialize |
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" |
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! ! |
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!LargeFloat class methodsFor:'constants'! |
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NaN |
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^ NaN |
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" |
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LargeFloat NaN |
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(0.0 uncheckedDivide:0.0) |
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" |
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! |
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infinity |
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^ PositiveInfinity |
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" |
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LargeFloat infinity |
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(1.0 uncheckedDivide:0.0) |
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" |
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! |
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negativeInfinity |
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^ NegativeInfinity |
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" |
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LargeFloat negativeInfinity |
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(-1.0 uncheckedDivide:0.0) |
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" |
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! |
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215 |
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pi |
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Pi_1000 isNil ifTrue:[ |
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Pi_1000 := FixedPoint pi asLargeFloat |
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]. |
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^ Pi_1000. |
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" |
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LargeFloat pi |
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" |
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! |
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unity |
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^ One |
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" |
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LargeFloat unity |
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" |
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! |
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zero |
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^ Zero |
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" |
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LargeFloat zero |
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" |
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! ! |
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242 |
||
8634 | 243 |
!LargeFloat class methodsFor:'queries'! |
244 |
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radix |
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"answer the radix of a LargeFloats exponent" |
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^ 2 |
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! ! |
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250 |
||
7445 | 251 |
!LargeFloat methodsFor:'accessing'! |
252 |
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exponent |
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^ exponent |
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! |
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256 |
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mantissa |
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^ mantissa |
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! |
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260 |
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precision |
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^ precision ? 200 |
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! ! |
|
264 |
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!LargeFloat methodsFor:'arithmetic'! |
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* aNumber |
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^ aNumber productFromLargeFloat:self |
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! |
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270 |
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+ aNumber |
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^ aNumber sumFromLargeFloat:self |
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273 |
||
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" |
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1.0 asLargeFloat |
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" |
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! |
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278 |
||
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- aNumber |
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^ aNumber differenceFromLargeFloat:self |
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! |
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282 |
||
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/ aNumber |
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^ aNumber quotientFromLargeFloat:self |
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! |
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286 |
||
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negated |
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mantissa = 0 ifTrue:[ |
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exponent = 0 ifTrue:[ ^ self ]. |
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self == NaN ifTrue:[^ self]. |
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self == NegativeInfinity ifTrue:[^ PositiveInfinity]. |
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^ NegativeInfinity |
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]. |
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294 |
||
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^ self class |
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mantissa:(mantissa negated) |
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exponent:exponent |
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7459 | 298 |
precision:self precision. |
7445 | 299 |
|
300 |
" |
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LargeFloat unity negated |
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302 |
" |
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! ! |
|
304 |
||
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!LargeFloat methodsFor:'coercing & converting'! |
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306 |
||
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asInteger |
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"return an integer with same value - might truncate" |
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309 |
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exponent = 0 ifTrue:[^ mantissa]. |
|
311 |
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312 |
mantissa == 0 ifTrue:[ |
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"/ INF or NAN |
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314 |
^ self class |
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315 |
raise:#domainErrorSignal |
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receiver:self |
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selector:#asInteger |
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arguments:#() |
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319 |
errorString:'Cannot represent non-finite as integer'. |
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"/ ^ self asMetaNumber. |
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321 |
]. |
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322 |
||
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exponent > 0 ifTrue:[ |
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^ mantissa * (2 raisedTo:exponent) |
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]. |
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^ mantissa // (2 raisedTo:exponent negated) |
|
327 |
||
328 |
" |
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(self new exponent:0 mantissa:100) asInteger |
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330 |
(self new exponent:1 mantissa:100) asInteger |
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331 |
(self new exponent:-1 mantissa:100) asInteger |
|
332 |
" |
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! |
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334 |
||
335 |
asLargeFloat |
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336 |
"return a large float with same value - thats me" |
|
337 |
||
338 |
^ self |
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! |
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340 |
||
341 |
asTrueFraction |
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342 |
"Answer a fraction or integer that EXACTLY represents self." |
|
343 |
||
344 |
exponent = 0 ifTrue: [ ^ mantissa]. |
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345 |
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346 |
mantissa == 0 ifTrue:[ |
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347 |
"/ INF or NAN |
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348 |
^ self class |
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raise:#conversionErrorSignal |
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350 |
receiver:self |
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351 |
selector:#asTrueFraction |
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arguments:#() |
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errorString:'Cannot represent non-finite float as fraction'. |
|
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"/ ^ self asMetaNumber. |
|
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]. |
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356 |
||
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exponent > 0 ifTrue: [ |
|
7552 | 358 |
^ mantissa bitShift:exponent |
7445 | 359 |
]. |
7552 | 360 |
^ Fraction |
361 |
numerator: mantissa |
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362 |
denominator: (1 bitShift:exponent negated) |
|
7445 | 363 |
|
364 |
" |
|
365 |
0.3 asFloat asTrueFraction |
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366 |
0.3 asShortFloat asTrueFraction |
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367 |
0.3 asLongFloat asTrueFraction |
|
368 |
0.3 asLargeFloat asTrueFraction |
|
369 |
||
370 |
1 asLargeFloat asTrueFraction |
|
371 |
2 asLargeFloat asTrueFraction |
|
372 |
0.5 asLargeFloat asTrueFraction |
|
373 |
||
374 |
0.25 asLargeFloat asTrueFraction |
|
375 |
-0.25 asLargeFloat asTrueFraction |
|
376 |
0.125 asLargeFloat asTrueFraction |
|
377 |
-0.125 asLargeFloat asTrueFraction |
|
378 |
||
379 |
1.25 asLargeFloat asTrueFraction |
|
380 |
3e37 asLargeFloat asTrueFraction |
|
381 |
||
382 |
LargeFloat NaN asTrueFraction -> error |
|
383 |
LargeFloat infinity asTrueFraction -> error |
|
384 |
LargeFloat negativeInfinity asTrueFraction -> error |
|
385 |
" |
|
386 |
! |
|
387 |
||
388 |
coerce:aNumber |
|
389 |
"return the argument as a LargeFloat" |
|
390 |
||
391 |
^ aNumber asLargeFloat |
|
392 |
! |
|
393 |
||
394 |
generality |
|
395 |
"return the generality value - see ArithmeticValue>>retry:coercing:" |
|
396 |
||
397 |
^ 100 |
|
398 |
! ! |
|
399 |
||
400 |
!LargeFloat methodsFor:'comparing'! |
|
401 |
||
402 |
< aNumber |
|
403 |
"return true, if the argument is greater" |
|
404 |
||
405 |
^ aNumber lessFromLargeFloat:self |
|
406 |
! |
|
407 |
||
408 |
= aNumber |
|
409 |
"return true, if the argument is equal in value" |
|
410 |
||
411 |
^ aNumber equalFromLargeFloat:self |
|
412 |
||
413 |
" |
|
414 |
LargeFloat unity = LargeFloat zero |
|
415 |
LargeFloat unity = LargeFloat unity |
|
416 |
||
417 |
LargeFloat unity = nil |
|
418 |
LargeFloat unity ~= nil |
|
419 |
" |
|
420 |
! |
|
421 |
||
422 |
hash |
|
423 |
"return a number for hashing; redefined, since floats compare |
|
424 |
by numeric value (i.e. 3.0 = 3), therefore 3.0 hash must be the same |
|
425 |
as 3 hash." |
|
426 |
||
427 |
exponent == 0 ifTrue:[^ mantissa hash]. |
|
428 |
exponent < 64 ifTrue:[^ (mantissa bitShift:exponent) hash ]. |
|
429 |
^ mantissa hash bitXor:exponent hash |
|
430 |
||
431 |
" |
|
432 |
LargeFloat unity hash |
|
433 |
LargeFloat zero hash |
|
434 |
||
435 |
3 hash |
|
436 |
3.0 hash |
|
437 |
3.1 hash |
|
438 |
3.14159 hash |
|
439 |
31.4159 hash |
|
440 |
3.141591 hash |
|
441 |
1.234567890123456 hash |
|
442 |
1.234567890123457 hash |
|
443 |
Set withAll:#(3 3.0 99 99.0 3.1415) |
|
444 |
" |
|
445 |
! ! |
|
446 |
||
447 |
!LargeFloat methodsFor:'double dispatching'! |
|
448 |
||
449 |
differenceFromLargeFloat:aLargeFloat |
|
450 |
|otherExponent otherMantissa e m| |
|
451 |
||
452 |
otherExponent := aLargeFloat exponent. |
|
453 |
otherMantissa := aLargeFloat mantissa. |
|
454 |
||
455 |
otherMantissa == 0 ifTrue:[ |
|
456 |
otherExponent = 0 ifTrue:[^ self negated]. |
|
457 |
"/ INF or NaN |
|
458 |
aLargeFloat isNaN ifTrue:[^ NaN]. |
|
459 |
self isFinite ifTrue:[^ aLargeFloat]. |
|
460 |
aLargeFloat sign ~~ self sign ifTrue:[^ self negated]. |
|
461 |
^ NaN |
|
462 |
]. |
|
463 |
mantissa == 0 ifTrue:[ |
|
464 |
exponent = 0 ifTrue:[^ aLargeFloat]. |
|
465 |
"/ INF or NaN |
|
466 |
self isNaN ifTrue:[^ NaN]. |
|
467 |
^ self negated |
|
468 |
]. |
|
469 |
||
470 |
otherExponent = exponent ifTrue:[ |
|
471 |
m := otherMantissa - mantissa. |
|
472 |
e := exponent |
|
473 |
] ifFalse:[ |
|
474 |
otherExponent> exponent ifTrue:[ |
|
475 |
m := (otherMantissa bitShift:(otherExponent-exponent)) - mantissa. |
|
476 |
e := exponent |
|
477 |
] ifFalse:[ |
|
478 |
m := otherMantissa - (mantissa bitShift:(exponent-otherExponent)). |
|
479 |
e := otherExponent |
|
480 |
] |
|
481 |
]. |
|
482 |
^ self class |
|
483 |
mantissa:m |
|
484 |
exponent:e |
|
7550 | 485 |
precision:(self precision min:aLargeFloat precision) |
7445 | 486 |
! |
487 |
||
488 |
equalFromLargeFloat:aLargeFloat |
|
489 |
aLargeFloat exponent = exponent ifTrue:[ |
|
490 |
^ aLargeFloat mantissa = mantissa |
|
491 |
]. |
|
492 |
"assuming normalized numbers, they cannot be equal then" |
|
493 |
^ false |
|
494 |
! |
|
495 |
||
496 |
lessFromLargeFloat:aLargeFloat |
|
497 |
|otherExponent otherMantissa| |
|
498 |
||
499 |
otherExponent := aLargeFloat exponent. |
|
500 |
otherMantissa := aLargeFloat mantissa. |
|
501 |
||
502 |
otherExponent > exponent ifTrue:[ |
|
503 |
^ otherMantissa < (mantissa bitShift:(otherExponent-exponent)) |
|
504 |
]. |
|
505 |
otherExponent < exponent ifTrue:[ |
|
506 |
^ (otherMantissa bitShift:(exponent-otherExponent)) < mantissa |
|
507 |
]. |
|
508 |
^ otherMantissa < mantissa |
|
509 |
! |
|
510 |
||
511 |
productFromLargeFloat:aLargeFloat |
|
512 |
|otherMantissa otherExponent| |
|
513 |
||
514 |
otherMantissa := aLargeFloat mantissa. |
|
515 |
otherExponent := aLargeFloat exponent. |
|
516 |
||
517 |
otherMantissa == 0 ifTrue:[ |
|
518 |
otherExponent ~= 0 ifTrue:[ |
|
519 |
"/ INF or NaN |
|
520 |
aLargeFloat isNaN ifTrue:[^ NaN]. |
|
521 |
self negative ifTrue:[^ aLargeFloat negated]. |
|
522 |
^ aLargeFloat |
|
523 |
]. |
|
524 |
]. |
|
525 |
mantissa == 0 ifTrue:[ |
|
526 |
exponent = 0 ifTrue:[^ self]. |
|
527 |
"/ INF or NaN |
|
528 |
self isNaN ifTrue:[^ NaN]. |
|
529 |
aLargeFloat negative ifTrue:[^ self negated]. |
|
530 |
^ self |
|
531 |
]. |
|
532 |
||
533 |
^ self class |
|
534 |
mantissa:(mantissa * otherMantissa) |
|
535 |
exponent:(exponent + otherExponent) |
|
7550 | 536 |
precision:(self precision min:aLargeFloat precision) |
7445 | 537 |
! |
538 |
||
539 |
quotientFromLargeFloat:aLargeFloat |
|
540 |
"Return the quotient of the argument, aLargeFloat and the receiver. |
|
541 |
Sent when aLargeFloat does not know how to divide by the receiver." |
|
542 |
||
543 |
|otherMantissa otherExponent q| |
|
544 |
||
545 |
otherMantissa := aLargeFloat mantissa. |
|
546 |
otherExponent := aLargeFloat exponent. |
|
547 |
||
548 |
otherMantissa == 0 ifTrue:[ |
|
549 |
otherExponent = 0 ifTrue:[^ aLargeFloat]. |
|
550 |
"/ INF or NaN |
|
551 |
aLargeFloat isNaN ifTrue:[^ NaN]. |
|
552 |
self negative ifTrue:[^ aLargeFloat negated]. |
|
553 |
^ aLargeFloat |
|
554 |
]. |
|
555 |
mantissa == 0 ifTrue:[ |
|
556 |
exponent = 0 ifTrue:[^ self]. |
|
557 |
"/ INF or NaN |
|
558 |
self isNaN ifTrue:[^ NaN]. |
|
559 |
aLargeFloat negative ifTrue:[^ self negated]. |
|
560 |
^ self |
|
561 |
]. |
|
562 |
q := (otherMantissa / mantissa). |
|
563 |
q isInteger ifFalse:[ |
|
564 |
self halt. |
|
565 |
]. |
|
566 |
^ self class |
|
567 |
mantissa:q |
|
568 |
exponent:(otherExponent - exponent) |
|
569 |
! |
|
570 |
||
571 |
sumFromLargeFloat:aLargeFloat |
|
572 |
|otherExponent otherMantissa e m| |
|
573 |
||
574 |
otherExponent := aLargeFloat exponent. |
|
575 |
otherMantissa := aLargeFloat mantissa. |
|
576 |
||
577 |
otherMantissa == 0 ifTrue:[ |
|
578 |
otherExponent = 0 ifTrue:[^ self]. |
|
579 |
"/ INF or NaN |
|
580 |
aLargeFloat isNaN ifTrue:[^ NaN]. |
|
581 |
self isFinite ifTrue:[^ aLargeFloat]. |
|
582 |
aLargeFloat sign == self sign ifTrue:[^ aLargeFloat]. |
|
583 |
^ NaN |
|
584 |
]. |
|
585 |
mantissa == 0 ifTrue:[ |
|
586 |
exponent = 0 ifTrue:[^ aLargeFloat]. |
|
587 |
"/ INF or NaN |
|
588 |
self isNaN ifTrue:[^ NaN]. |
|
589 |
^ self |
|
590 |
]. |
|
591 |
||
592 |
otherExponent = exponent ifTrue:[ |
|
593 |
m := otherMantissa + mantissa. |
|
594 |
e := exponent |
|
595 |
] ifFalse:[ |
|
596 |
otherExponent> exponent ifTrue:[ |
|
597 |
m := (otherMantissa bitShift:(otherExponent-exponent)) + mantissa. |
|
598 |
e := exponent |
|
599 |
] ifFalse:[ |
|
600 |
m := otherMantissa + (mantissa bitShift:(exponent-otherExponent)). |
|
601 |
e := otherExponent |
|
602 |
] |
|
603 |
]. |
|
604 |
^ self class |
|
605 |
mantissa:m |
|
606 |
exponent:e |
|
7550 | 607 |
precision:(self precision min:aLargeFloat precision) |
7445 | 608 |
! ! |
609 |
||
610 |
!LargeFloat methodsFor:'printing'! |
|
611 |
||
612 |
printOn:aStream |
|
613 |
exponent == 0 ifTrue:[ |
|
614 |
mantissa printOn:aStream. |
|
615 |
aStream nextPutAll:'.0'. |
|
616 |
^ self |
|
617 |
]. |
|
618 |
mantissa == 0 ifTrue:[ |
|
619 |
self == NaN ifTrue:[ aStream nextPutAll:'NAN'. ^ self ]. |
|
620 |
self == NegativeInfinity ifTrue:[ aStream nextPutAll:'-INF'. ^ self]. |
|
621 |
self == PositiveInfinity ifTrue:[ aStream nextPutAll:'INF'. ^ self]. |
|
7550 | 622 |
self error:'invalid largeFloat' mayProceed:true. |
623 |
aStream nextPutAll:'Invalid'. ^ self. |
|
7445 | 624 |
]. |
625 |
||
626 |
exponent > 0 ifTrue:[ |
|
7550 | 627 |
self halt. |
7445 | 628 |
(mantissa bitShift:exponent) printOn:aStream. |
629 |
aStream nextPutAll:'.0'. |
|
630 |
^ self |
|
631 |
]. |
|
632 |
((mantissa / (1 bitShift:exponent negated)) asFixedPoint:6) printOn:aStream. |
|
7550 | 633 |
|
634 |
" |
|
635 |
||
636 |
" |
|
7445 | 637 |
! ! |
638 |
||
639 |
!LargeFloat methodsFor:'private'! |
|
640 |
||
641 |
mantissa:mantissaArg exponent:exponentArg |
|
7546 | 642 |
"set instance variables. |
643 |
Notice, that the floats value is m * 2^e" |
|
7445 | 644 |
|
645 |
exponent := exponentArg. |
|
646 |
mantissa := mantissaArg. |
|
7550 | 647 |
precision := Infinity positive. |
7445 | 648 |
self normalize. |
649 |
! |
|
650 |
||
651 |
mantissa:mantissaArg exponent:exponentArg precision:precisionArg |
|
7546 | 652 |
"set instance variables. |
653 |
Notice, that the floats value is m * 2^e" |
|
654 |
||
7445 | 655 |
exponent := exponentArg. |
656 |
mantissa := mantissaArg. |
|
657 |
precision := precisionArg. |
|
658 |
self normalize |
|
659 |
! |
|
660 |
||
661 |
normalize |
|
662 |
"adjust m & e such that m is the smallest possible |
|
7546 | 663 |
(i.e. has no least significant zero bit). |
664 |
Notice, that the floats value is m * 2^e" |
|
7445 | 665 |
|
666 |
|shift| |
|
667 |
||
668 |
shift := mantissa lowBit - 1. |
|
669 |
shift > 0 ifTrue:[ |
|
670 |
mantissa := mantissa bitShift:shift negated. |
|
671 |
exponent := exponent + shift |
|
672 |
]. |
|
673 |
||
674 |
" |
|
7546 | 675 |
self mantissa:1 exponent:0 |
676 |
self mantissa:2 exponent:0 |
|
677 |
self mantissa:4 exponent:0 |
|
678 |
self mantissa:8 exponent:0 |
|
679 |
self mantissa:10 exponent:-1 |
|
680 |
self mantissa:10 exponent:0 |
|
681 |
self mantissa:10 exponent:1 |
|
7445 | 682 |
" |
683 |
! ! |
|
684 |
||
8634 | 685 |
!LargeFloat methodsFor:'queries'! |
686 |
||
687 |
epsilon |
|
688 |
"answer the radix of a LargeFloats exponent" |
|
689 |
||
690 |
|p| |
|
691 |
||
692 |
p := precision. |
|
693 |
p isFinite ifTrue:[ |
|
694 |
^ self class radix asFloat raisedTo:(1 - p) |
|
695 |
]. |
|
696 |
"/ mhmh - what should we use here ??? |
|
697 |
^ LongFloat epsilon |
|
698 |
! ! |
|
699 |
||
7445 | 700 |
!LargeFloat methodsFor:'testing'! |
701 |
||
702 |
isFinite |
|
703 |
^ mantissa ~= 0 or:[exponent = 0] |
|
704 |
! |
|
705 |
||
706 |
isInfinite |
|
707 |
^ mantissa = 0 and:[exponent ~= 0] |
|
708 |
! |
|
709 |
||
710 |
isNaN |
|
711 |
^ self == NaN |
|
712 |
! |
|
713 |
||
714 |
isZero |
|
715 |
^ self == Zero |
|
716 |
! |
|
717 |
||
718 |
negative |
|
719 |
"return true if the receiver is negative" |
|
720 |
||
721 |
mantissa == 0 ifTrue:[ ^ exponent negative]. |
|
722 |
^ mantissa negative |
|
723 |
! |
|
724 |
||
725 |
sign |
|
726 |
"return the sign of the receiver" |
|
727 |
||
7546 | 728 |
mantissa == 0 ifTrue:[ |
729 |
"special value for infinites" |
|
730 |
^ exponent sign |
|
731 |
]. |
|
7445 | 732 |
^ mantissa sign |
733 |
! ! |
|
734 |
||
735 |
!LargeFloat class methodsFor:'documentation'! |
|
736 |
||
737 |
version |
|
17883
209190914636
svn:keywords property set correctly
Jan Vrany <jan.vrany@fit.cvut.cz>
parents:
17846
diff
changeset
|
738 |
^ '$Id: LargeFloat.st 10717 2011-10-11 15:53:59Z vranyj1 $' |
7445 | 739 |
! ! |
740 |
||
17846 | 741 |
LargeFloat initialize! |