Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uwm.edu!ux1.cso.uiuc.edu!iuvax!noose.ecn.purdue.edu!dynamo.ecn.purdue.edu!dmc From: dmc@dynamo.ecn.purdue.edu (David M Chelberg) Newsgroups: comp.lang.lisp Subject: AKCL and internal representations of data types Keywords: AKCL, lisp, data types Message-ID: <1990Aug10.221006.5847@ecn.purdue.edu> Date: 10 Aug 90 22:10:06 GMT Sender: news@ecn.purdue.edu (USENET news) Reply-To: dmc@dynamo.ecn.purdue.edu Organization: Purdue University Lines: 22 Is there somewhere which documents the storage various data types require? In an old version of AKCL arrays of type '(mod 256) used to take up just one byte of storage. Now in version 1.473 they appear to take up 4 bytes and appear to be internally typed as fixnums. Is there some way to get back to the old representation? Or is there an alternate type definition I could use when creating the array to insure only one byte of storage is used. This becomes extremely important when passing arrays to C language routines. I have found that characters take only one byte, but then I am constantly using code-char and char-code to convert to numbers, although C doesn't seem to care. I hope that there is some way to coerce AKCL into using only one byte to represent numbers. My problem domain is image understanding and processing. When you have many large images, representing them efficiently is important. __ _ _ _ __ _ / ) / ' ) ) ) / ) / // / / / __. , __o __/ / / / / /_ _ // /___/> __ _, /__/_(_/|_\/ <__(_/_ / ' ( o (__/ / /_