Subject: CFITSIO 2.0 Update

From: William Pence <pence at tetra.gsfc.nasa.gov>
Date: Tue, 02 Mar 1999 12:45:21 -0500

.                     **** CFITSIO v2.0 Release ****

This is an update on the latest features that have been added to version
2.0 of the CFITSIO library for reading and writing FITS files, which is
available at

     http://heasarc.gsfc.nasa.gov/fitsio

1.  Any table column, regardless of the datatype, can be read as a
character string.  The format of the returned string is determined by the
TDISPn display format keyword if it exists, otherwise a default format 
based on the datatype of the column is used.

2.  A subsection of a FITS image can be opened by appending the starting
and ending pixel numbers (and optionally, a pixel increment) for each
dimension to the filename with the IRAF-style syntax: 

   filename.fits[xstart:xend:xstep, ystart:yend:ystep]

For example, "myfile.fits[1:512:2, 2:512:2]" will open a 256x256 pixel
image consisting of the odd numbered columns and the even numbered rows of
the input image.

3.  Added transparent support for the ESO HIERARCH keyword convention for
keyword names longer than 8 characters or that contain ASCII characters not
allowed in normal FITS keywords.  Thus, CFITSIO can effectively read and
write keywords like:

     heliocentric_correction = -45.5   / velocity
     HST WFPC2 Exposure Time = 1200.0  / exposure time in seconds
     heater:temp:#34 = 0.8  / degrees C

These types of keywords are stored in the FITS header using the HIERARCH
keyword convention that fully conforms to the FITS Standard.

4.  Added new support routines for dealing with World Coordinate System
keywords, which makes it easier to call Doug Mink's WCSlib routines for
converting between plate and sky coordinates. 

5.  Added support for opening images or arrays that are contained in a
single cell of a binary table, with the syntax:

     "filename.fits[extname; col_name(row_number)]" 

where 'extname' is the name of the table extension, 'col_name' is the name
of the column and 'row_number' is the number of the row in the table that
contains the array.  This array is opened so that it appears to the
application program as though it is opening a FITS image in the primary
array.

6.  Added 2 new routines to read any consecutive string of bits as an
unsigned integer from a Bit 'X' or Byte 'B' column.

7.  Added support for VMS-style directories in the input file name 
(e.g. "disk:[user.subdir]myfile.fits").

8.  Added supporting project files and instructions for building CFITSIO
under Windows NT with the Microsoft Visual C++ compiler.

9.  Made major improvements to both the C and Fortran User's Guides.  These
Guides are available on line at:
 C: http://legacy.gsfc.nasa.gov/docs/software/fitsio/c/c_user/cfitsio.html
 Fortran:
    http://legacy.gsfc.nasa.gov/docs/software/fitsio/c/f_user/fitsio.html

As a reminder, version 2.0 of CFITSIO also supports these features:

1.  CFITSIO can read IRAF format image files (.imh files) as well as
    FITS files. Thus, any program that uses CFITSIO to do image analysis
    of FITS images can directly read IRAF images as well.

2.  FITS files on the internet can be directly read by providing the
    full FTP or HTTP URL as the input file name.

3.  Input FITS files can be filtered or modified at run-time based on a
    user-supplied expression that is appended to the name of the input
    file.  This allows users, at run time, to:

  a) select a subset of the rows in a table which satisfy an 
     arbitrarily complex boolean expression

  b) create new table columns whose values are calculated 
     as a function of other columns and/or keywords in the table

  c) create a virtual FITS image by binning/histogramming
     the values in one or more table columns.  This is most often 
     used to create an image by binning a list of X and Y coordinates
     for each event in a table.

4.  The data input and output routines in CFITSIO has been optimized 
    to achieve high throughputs, with typical rates of 5 - 10 MB/s
    on current generation machines.

Many people and institutions have contributed to these new features in
CFITSIO:  Please refer to the User's Guides for the list of
acknowlegements.
-- 
____________________________________________________________________
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)