Reading and writing doubles

From: Chris Cowley (ccowley_at_swenA-fodder.grok.co.uk)
Date: 10/16/03 

Date: Thu, 16 Oct 2003 17:22:19 +0100

What is the most efficient way to set and read the value of 'double'
floating point values in Delphi (v5 in case that matters) using the
internal 8-byte exponent+manstissa representation?

At the moment I am using a TMemoryStream to convert between a double and
an array of bytes, like this:-

        var
         ms: TMemoryStream;
         z: double;
         b: array[0..7] of byte;
        egin
         z := 3.141592;
        
         ms := TMemoryStream.Create;
         ms.Write(z,8);
         ms.Seek(0,soFromBeginning);
         ms.Read(b,8);
         ms.Free;

This works, but I can't help but feel there must be a much more
efficient way of doing it, using a pointer to the double or something.
Any ideas?

Thanks. 

-- 
Chris Cowley
 ccowley @ grok.co.uk

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