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Re: Accessing bits in a floating point number [message #10427 is a reply to message #10424]

Fri, 21 November 1997 00:00

Kevin Ivory
Messages: 71
Registered: January 1997

Member

Brian Chafin wrote:
> I am reading a 16-bit floating point number from an HDF file. This
> 16-bit number was originally two 1-byte integers which were stuffed into
> a 16-bit float. This was done in C and don't ask why it was done this
> way.
>
> When the float is read into IDL using the native IDL HDF commands, the
> result is a 32-bit float.
>
> Is there any way to extract the original two 1-byte integers from this
> IDL float?

I have never heard of or used 16 bit floats, but if you want to reverse
the 32 bit float to a 16 bit float it seems you will have to know the
bit positioning of both. I am not familiar with HDF either, but in a
normal binary file I would read of either a 16 bit integer and
do the byte-extracting from that or read the two 8 bit integers straight
out of the file. How about giving the HDF declaration the data type
INT DFNT_INT16 and going on from there?

Best regards
Kevin
--
Kevin Ivory Tel: +49 5556 979 434
Max-Planck-Institut fuer Aeronomie Fax: +49 5556 979 240
Max-Planck-Str. 2 mailto:Kevin.Ivory@linmpi.mpg.de
D-37191 Katlenburg-Lindau, GERMANY http://www.gwdg.de/~kivory2/

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[Message index]

		Re: Accessing bits in a floating point number By: Thomas A. McGlynn on Fri, 21 November 1997 00:00
		Re: Accessing bits in a floating point number By: Kevin Ivory on Fri, 21 November 1997 00:00

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