How to do bit manipulation in VBA?

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curiousgeorge408@hotmail.com - 24 Nov 2007 19:13 GMT

I want to pass a floating-point number to a VBA function and access
the binary representation. In C, I might declare a union of double
and 8-element unsigned char array, assign the function parameter to
the double, then access the bits of the unsigned char array.
Alternatively, I might use memcpy() to copy the floating-point
parameter into an 8-element unsigned char array.

How can I accomplish that (either one) in VBA?

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Gary''s Student - 24 Nov 2007 20:09 GMT

Hi George:

http://groups.google.com/group/microsoft.public.excel.programming/browse_thread/
thread/bf59cb8c21444f5f/486d0799a6ef6d0a?lnk=st&q=%22bit+manipulation+group%3A*e
xcel#

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Gary''s Student - gsnu2007a

> I want to pass a floating-point number to a VBA function and access
> the binary representation. In C, I might declare a union of double
[quoted text clipped - 4 lines]
>
> How can I accomplish that (either one) in VBA?

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curiousgeorge408@hotmail.com - 25 Nov 2007 01:52 GMT

On Nov 24, 12:09 pm, Gary''s Student
<GarysStud...@discussions.microsoft.com> wrote:

> http://groups.google.com/group/microsoft.public.excel.programming/bro...

Thanks for the pointer. (Sigh, Google Groups seems to be truncating
the URL in this response.)

I did see this thread when I searched GG before posting my inquiry.
But I was unable to look at threads from early 2005 and earlier,
including this one. I ass-u-me-d that GG kept the NG index, but not
the articles. (I thought that was odd, but I imagined a dubious
benefit.) But after I clicked on your link, I discovered that all the
links in the search result now work. I'm sure it has nothing to do
with clicking on your link. The earlier failure must've been a hiccup
in the GG intranet. Klunk! I'll try to be more patient in the
future.

Anyway, this is a great(!) pointer. It sparks some follow-up
questions, which are non-technical. I hope someone will be kind
enough to offer some insight.

First, where can I learn (more) about the user-callable entry points
in the Kernel32 lib -- and any other system libs that might be
accessible to VBA programs?

I don't 'spose there are "man pages" <wink>.

(My VBA book does mention some useful entry points and how to use
them. But it is not complete, by a long shot.)

Second, where can I learn (more) about the VBA language?

I'm looking for the "K&R" of VBA <wink>.

My VBA book, which is one of the most recommended in these NGs, does
not mention LSET, for example. At least, not that I recall. The
book's index is terrible. So it is possible that LSET is mentioned in
context somewhere, and I simply can no longer find it (like almost
everything else), having no idea in what context the author chooses to
introduce what <sigh>.

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Gary''s Student - 25 Nov 2007 13:21 GMT

Hi George:

For API info you might checkout Ivan Moala's site:

http://www.xcelfiles.com/Index.html

or

http://www.answers.com/library/Win+APIs

or

http://www.andreavb.com/API_USER32.html

Have fun with this !

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Gary''s Student - gsnu2007b

> On Nov 24, 12:09 pm, Gary''s Student
> <GarysStud...@discussions.microsoft.com> wrote:
[quoted text clipped - 36 lines]
> everything else), having no idea in what context the author chooses to
> introduce what <sigh>.

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curiousgeorge408@hotmail.com - 26 Nov 2007 07:56 GMT

On Nov 25, 5:21 am, Gary''s Student
<GarysStud...@discussions.microsoft.com> wrote:

> http://www.answers.com/library/Win+APIs

Thanks for the pointers.

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