Re: Common and uncommon goals and software

[Andrew Bennett <andrew.bennett@ns.sympatico.ca>]

On Fri, 3 Nov 2000 16:28:52 -0500, Stupendous Man 
<richmond@a188-l009.rit.edu> wrote:

>
>  Robert asks a question that many of us have pondered:
>...
>  There may also be secondary considerations which prevent us all from
>settling on one piece of software:
>
>       - preferences for specific algorithms (e.g. PSF-fitting versus
>                 aperture photometry)
Secondary?!!!
Sir! You are thus dismissing matters of religious significance!

>       - different reference catalogs
A serious matter.
The "solution" I am using at the moment is to process the
messy and incomprehensible (not to say inconsistent e.g. Tycho2) 
format of the original catalog, a chunk at a time in my trusty 
spreadsheet, into a clear, concise ASCII text file and write 
beautifully clear universal code to read this.

Unfortunately, each new catalog adds some new feature which
I must have. Tycho2 adds proper motions, which are absolutely
essential. My beautifully clear universal code then gets a few
bits hung on to cope with the new information ... ending up
a little less than clear and absolutely guaranteed to be not
universal.

>       - different interests (e.g. variable stars vs. an all-sky 
>                 photometric survey)
>       - general pigheadedness: we don't believe that software written
>                 by someone else is as good as our own
As in "I am resolute; you are stubborn; he is pigheaded."

I resolutely believe there are still problems to be solved in
flat-fielding before the data is good enough for me to use (for
whatever purpose ...) and that nobody else's pipeline properly
addresses this problem. Come to think of it, nor does mine.

>
>  I suspect that these are less important than the environment issue.
No way.
If somebody has a system in COBOL or LISP that does the job
and is accepted to do the job, it will miraculously turn up
in FORTH or PASCAL or whatever ... even in C under UNIX!

>  There is a software package used by many different astronomers
>to reduce and analyze data from many different instruments.  It is 
>called "IRAF", and you can read about it, and download it, from
>
>               http://iraf.noao.edu
>
>I have used IRAF in the past to reduce optical images, and I do have
>a copy installed on my computer here at work.  But I shrink from the 
>prospect of using it to reduce Mark IV data.  Why?  Well, mostly
>because I don't understand exactly what it does. 

You are absolutely right! Science can not be done using
a proprietory package with unexplained algorithms. Science
cannot be done even with a completely open, public system if
the documentation has grown so big that one human cannot in one
lifetime get through all of it ... and several public domain
C packages come into this category!
> IRAF is so big 
>that it acts like a "black box" to most users.

Or a black hole.

Andrew Bennett, Avondale Vineyard, Nova Scotia, Canada.