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"
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COPYRIGHT (c) 1993 by Claus Gittinger
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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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ArrayedCollection variableDoubleSubclass:#DoubleArray
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instanceVariableNames:''
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classVariableNames:''
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poolDictionaries:''
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category:'Collections-Arrayed'
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1
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!
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!DoubleArray class methodsFor:'documentation'!
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copyright
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"
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COPYRIGHT (c) 1993 by Claus Gittinger
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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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362
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DoubleArrays store doubleFloats values (and nothing else).
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They have been added to support heavy duty number crunching somewhat
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better than other smalltalks do.
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362
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Storing Floats & Doubles in these objects (instead of Arrays)
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has some benefits:
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1) since the values are stored directly (instead of pointers to them)
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both access overhead and garbage collect overhead is minimized.
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2) they can be much faster passed to c functions (such as graphics
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libraries or heavy duty math packages), since the double values
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come packed and can be used in C by using a (double *) or double[].
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362
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There is no need to loop over the array extracting doubles.
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3) they could (in theory) be much more easily be processed by things like
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vector and array processors
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Be aware however, that Float- and DoubleArrays are not supported in other
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smalltalks - your program will thus become somewhat less portable.
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(since their protocol is the same as normal arrays filled with floats,
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they can of course be easily simulated - a bit slower though)
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However, they could be simulated by a ByteArray, using doubleAt: and
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doubleAtPut: messages to access the elements, but that seems a bit
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clumsy and unelegant. Also, the stc-compiler may learn how to deal
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with Float- and DoubleArrays, making accesses very fast in the future.
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Hint: if you use doubleArrays in your application and must port it
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to some other smalltalk, define a DoubleArray class there, which is derived
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from ByteArray, and add access methods.
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Of course, DoubleArray can be subclassed,
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and named instance variables can be added there.
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See example uses in the GLX interface and GLDemos.
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[See also:]
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FloatArray Array
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1290
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[author:]
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Claus Gittinger
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"
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! !
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!DoubleArray class methodsFor:'documentation'!
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565
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version
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^ '$Header: /cvs/stx/stx/libbasic/DoubleArray.st,v 1.17 1997-07-31 16:46:12 cg Exp $'
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! !
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