From owner-fitsbits at kochab.cv.nrao.edu  Wed Oct 13 10:56:35 1999
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To: fitsbits at cv.nrao.edu
Date: Wed, 13 Oct 1999 14:52:02 +0200
From: Eric Aristidi <aristidi at unice.fr>
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Subject: Read FITS from Octave/Matlab
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Hello,

Anybody knows wether it exists matlab function for reding FITS files ?

Thanks for help

-- 
Eric Aristidi
Dpt Astrophysique - Universite de Nice, Parc Valrose, 06108 Nice Cedex 2
mail   : aristidi at unice.fr
fax    : +33 4 92 07 63 21
phone  : +33 4 92 07 63 45
http://www-astro.unice.fr/PagePerso/aristidi/

From owner-fitsbits at kochab.cv.nrao.edu  Wed Oct 13 10:56:40 1999
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To: fitsbits at cv.nrao.edu
Date: 12 Oct 1999 21:29:42 GMT
From: "F.Cavicchio" <nospam at iol.it>
Message-ID: <01bf14f8$e2190a40$d887d8d4 at privato>
Organization: TIN
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Subject: Avis FITS Viewer
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Our new, freeware FITS Viewer AVIS is now available for
download at the following URL:

http://www.sira.it/msb/avis.htm

Features:

Opens FITS files: (8 & 16 bit), supports multiple file opening and drag &
drop from Explorer and other Windows shells. 

Imports CCD files: like SBIG ST8, ST7, ST6, ST5, ST4, Starlight, Hisis,
Pixcell and others. Imports graytones TIFF and TGA files. 

Saves FITS and allows modifications of the FITS Header. 

Exports files as TXT format, RAW, TIFF, TGA, BMP and JPEG. 

On-line help: full documentation about Avis and about FITS file format. 

Hi,
F.Cavicchio.

From owner-fitsbits at kochab.cv.nrao.edu  Wed Oct 13 11:15:32 1999
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To: Eric Aristidi <aristidi at unice.fr>
CC: fitsbits at nrao.edu
Subject: Re: Read FITS from Octave/Matlab
References: <38048072.DF9D7848 at unice.fr>
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There is a listing for a FITS Matlab library written by
Peter Rydesater in our table of FITS libraries at

   http://heasarc.gsfc.nasa.gov/docs/heasarc/fits/fits_libraries.html

I believe this library provides only support for FITS images.

	Regards,
	Tom McGlynn

Eric Aristidi wrote:
> 
> Hello,
> 
> Anybody knows wether it exists matlab function for reding FITS files ?
> 
> Thanks for help
> 
> --
> Eric Aristidi

From owner-fitsbits at kochab.cv.nrao.edu  Wed Oct 20 08:31:21 1999
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To: fitsbits at cv.nrao.edu
Date: Tue, 19 Oct 1999 23:08:46 GMT
From: "Martino Nicolini" <mnico at iol.it>
Message-ID: <2S6P3.27825$i06.315949 at typhoon.libero.it>
Organization: [Infostrada]
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Subject: [fitsbits] AVIS FITS viewer
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There is a new FITS viewer at the page:

http://www.sira.it/msb/avis.htm

AVIS is a freeware FITS viewer for Windows 95, 98 and NT.

Features:

- opens FITS files: (8 & 16 bit), supports multiple file opening and drag &
drop from  Explorer and other Windows shells;

- imports CCD files: like SBIG ST8, ST7, ST6, ST5, ST4, Starlight, Hisis,
Pixcell and others. Imports graytones TIFF and TGA files;

- saves FITS and allows easy and fast modifications of the FITS Header;

- exports files: as TXT format, RAW, TIF, TGA, BMP and JPEG;

- supports WCS (World Coordinates System);

- custom palettes;

- on-line help: full documentation about AVIS and introduction to FITS file
format.

Enjoy this Italian software!

Martino Nicolini
********************************************
OSS. ASTRONOMICO "G. MONTANARI" - CAVEZZO
via Concordia, 200 - 41032 Cavezzo (MO) ITALY
MPC 107
Tel. ++39 0535-58755
E-mail: oss_astr_cav at arcanet.it
WEB: http://www.arcanet.it/oss_astronomico/
Personal E-mail: mnico at iol.it
********************************************

From owner-fitsbits at kochab.cv.nrao.edu  Wed Oct 20 08:31:33 1999
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To: fitsbits at cv.nrao.edu
Date: Tue, 19 Oct 1999 21:55:02 -0700
From: jack_72 at hotmail.com (Jack Thomas)
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Subject: [fitsbits] best program
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What is the best program to work with fits formats (for a MacIntosh)?

Thanks

From owner-fitsbits at kochab.cv.nrao.edu  Mon Oct 25 15:35:57 1999
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To: fitsbits at cv.nrao.edu
Date: Mon, 25 Oct 1999 15:05:00 -0400
From: "Derek Schulze" <ds24 at post.queensu.ca>
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Subject: [fitsbits] importing FITs files...
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I am trying to find a way to get FITs files into any common viewer that
would be capable of appending the files together to form a single stacked
file of images (eg; NIH Image, ImageJ, ImageTool).  Could I make a MOV or
AVI out of a series of FITs files?

Anyone out there have any ideas?  Thanks.

From owner-fitsbits at kochab.cv.nrao.edu  Fri Oct 29 14:10:19 1999
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To: fitsbits at cv.nrao.edu
Date: Fri, 29 Oct 1999 10:21:55 -0400
From: Paul Barrett <barrett at stsci.edu>
Message-ID: <3819AD83.E38C006A at stsci.edu>
Organization: Space Telescope Science Institute, Baltimore, MD 21218
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Subject: [fitsbits] Some FITS ambiguities
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I have three questions about version 2.0 of the FITS standard that the
NOST document doesn't appear to cover.

1) What is the recommended procedure for handling a keyword value that
is >4294967296 (i.e. a 32-bit unsigned integer), or similarly,
>18446744073709551616 (ie. a 64-bit unsigned integer)?

Note that in fixed format an integer can have 20 digits. If they are all
9s, the integer is greater than a 64-bit unsigned integer.  And in free
format, integers can have 70 digits.  How are these numbers to be
handled?  By a BCD library?

2) What is the practical difference between a null string (i.e. '') and
a blank string (i.e. '        ')?  See page 16 of the FITS standard.
They are both strings. Does it really matter if one has 8 spaces and the
other 0 spaces?

3) The FITS standard notes that a series of digits with leading zeros is
considered a decimal number, not an octal number as found in many
programming languages.  (Kind of a shame really.)  The FITS standard
does not note whether this is also true for floating point numbers.  Can
floating point values contain leading zeros?

--
Dr. Paul Barrett       Space Telescope Science Institute
Phone: 410-516-6714    DESD/DPT
FAX:   410-516-8615    Baltimore, MD 21218

From owner-fitsbits at kochab.cv.nrao.edu  Fri Oct 29 18:56:25 1999
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To: Paul Barrett <barrett at stsci.edu>
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Subject: Re: [fitsbits] Some FITS ambiguities
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Paul Barrett wrote:
> 
> I have three questions about version 2.0 of the FITS standard that the
> NOST document doesn't appear to cover.

Here's my opinion:

> 1) What is the recommended procedure for handling a keyword value that
> is >4294967296 (i.e. a 32-bit unsigned integer), or similarly,
> >18446744073709551616 (ie. a 64-bit unsigned integer)?
>
> Note that in fixed format an integer can have 20 digits. If they are all
> 9s, the integer is greater than a 64-bit unsigned integer.  And in free
> format, integers can have 70 digits.  How are these numbers to be
> handled?  By a BCD library?

The FITS Standard does not restrict the range of integer keyword values, so you can write
as many digits as will fit on the line (70).  It is then an implementation detail as to
how such large values should be handled by FITS reading software.  This will probably vary
from application to application.

> 2) What is the practical difference between a null string (i.e. '') and
> a blank string (i.e. '        ')?  See page 16 of the FITS standard.
> They are both strings. Does it really matter if one has 8 spaces and the
> other 0 spaces?

Conceptually at least, there is a difference between the two:  a null string ('') is a
string that has a null or undefined value.  A blank string on the other hand has a defined
value that consists of a sequence of blanks.  The Standard says that trailing blanks are
not significant, so I would interpret the first blank to be significant and any following
blanks to be insignificant (others might disagree with this interpretation however). The
distinction between null and blank strings may be lost in some languages (e.g. Fortran 77)
which do not naturally support the concept of a null string.   A keyword should be given a
null string value if the value is unknown at the time of writing the keyword, but may be
possibly  updated at a later time with a known value.  A blank string should be used if it
is known that the string is blank (e.g. if a keyword gives the middle initial of the
observer, then it should be blank if the observer has no middle name, and null if it is
not known whether the observer has a middle name).  In practice, I doubt if this
distinction is very important, except in certain special applications which might want to
use it.

Note that there is yet a third case in which a keyword can have no value, e.g.

RVALUE  =                  / comment field

In this case the datatype as well as the value of the keyword are both undefined (unless
the keyword is specifically defined to have a certain datatype in the Standard).

> 3) The FITS standard notes that a series of digits with leading zeros is
> considered a decimal number, not an octal number as found in many
> programming languages.  (Kind of a shame really.)  The FITS standard
> does not note whether this is also true for floating point numbers.  Can
> floating point values contain leading zeros?

Yes.  The Standard does not explicitly mention this case because there is little ambiguity
about how to interpret the value of floating point numbers containing leading zeros,
unlike the integer case.

-Bill Pence
____________________________________________________________________
Dr. William Pence                          pence at tetra.gsfc.nasa.gov
NASA/GSFC Code 662         HEASARC         +1-301-286-4599 (voice)     
Greenbelt MD 20771                         +1-301-286-1684 (fax)