COPYRIGHT INFORMATION --------------------- All files in this distribution except for the C code in the slalib_src directory are protected by the following copyright declaration. Copyright (c) 1992 by the California Institute of Technology. Author: Martin C. Shepherd (mcs@astro.caltech.edu) or (15237::mcs) The C code in the slalib_src directory is included with permission from its author, Patrick Wallace. Slalib copying and usage restrictions are described in the README file in the slalib_src directory. Permission to copy the difmap distribution is granted for non-commercial purposes on the understanding that neither the author, nor Caltech shall be held responsible for any adverse consequences resulting from its use. Difmap must not be re-distributed in a modified form without the author's explicit permission. No assurance of suitability for any purpose is implied by its availability for copying. GENERAL INFORMATION ------------------- This is the second major version of Difmap. Instead of reading the Caltech VLBI merge format, this version reads UV FITS files directly. Support for UV FITS files is limited to single-source files containing one frequency-id (one set of possibly differing IF frequencies). Multiple sub-arrays, IFs, spectral-line channels and polarizations are now supported. Difmap version 2.3c should compile on the following systems: Architecture OS ANSI-C FORTRAN-77 PGPLOT compiler compiler status ------------ ----------- -------- ----------- ------------ Sparc SunOS 4.x gcc f77 Supported Sparc Solaris 2.x gcc f77 Supported Sparc Solaris 2.x SUN cc f77 Supported HP9000 700-800 HPUX c89 fort77 Supported IBM RS6000 AIX c89 xlf Supported Alpha-AXP OSF1 gcc f77 Supported PC Linux i486 gcc f77 Supported No other machines are currently supported. SHOPPING LIST ------------- To successfully install difmap you will need the following items: 1. One of the above combinations of OS and compilers. OR 1. An ANSI-C compiler (eg. gcc). You can get the gcc distribution via anonymous ftp from prep.ai.mit.edu in directory /pub/gnu/. 2. A FORTRAN-77 compiler. 3. PGPLOT at version 5.0.2 or above. This may be obtained via anonymous ftp from astro.caltech.edu (131.215.240.1) in directory /pub/pgplot/. Older versions of PGPLOT will not work with this version of Difmap. Note that PGPLOT 5.x is simpler to install than earlier versions. GETTING THE LATEST DISTRIBUTION OF DIFMAP ----------------------------------------- The latest version of difmap can be obtained via anonymous FTP from astro.caltech.edu (131.215.240.1). Supply the word, anonymous, as your username and send your email address as the corresponding password. Then, to get the compressed tar file of difmap, and the postscript version of the Difmap cookbook, type the following: ftp> cd pub/difmap ftp> get cookbook.ps.Z ftp> binary ftp> get difmap2.3c.tar.Z ftp> quit Then uncompress the tar file: uncompress difmap2.3c.tar.Z This will replace the compressed file with a file called difmap2.3c.tar. Now you should decide where you intend to compile difmap (This need not be the directory where difmap will eventually be installed, but you will require up to 10 Mega-bytes of disk space for compilation). Move to your chosen directory: cd wherever Then unpack the distribution: tar xf difmap2.3c.tar This will silently create a directory called ./uvf_difmap/ in your current directory. cd uvf_difmap/ You are now ready to configure and build Difmap. INSTALLATION INSTRUCTIONS ------------------------- To make difmap, perform the following steps: 1. You should find a bourne shell script called configure in the top level directory of the distribution. This script configures the make files for a particular site. Before running this file you must edit it. Follow the instructions in the configure file on what to change, [Probably only HELPDIR and PGPLOT_LIB]. Once you have edited the configure script, type: ./configure operating_system_name-compiler_name Recognized operating_system_name-compiler_name pairs are listed at the top of the ./configure file. For example to install difmap on a SUN running Solaris2.*, using the SUN ANSI C compiler, you would type: ./configure sol2-cc 2. You will also find a bourne shell script called makeall in the same directory as the file you are reading at the moment. This applies make in each of the source code directories. To run this type: ./makeall If the compilation fails, check your changes to ./configure and if you can't figure out the problem, send me an email displaying the compiler generated error codes and any other information that you can garner. On a SUN Sparc IPX running SunOS and using gcc, compilation takes roughly 11 minutes. 3. Move the help files to the directory named in the configure script. mkdir the_name_of_the_new_directory cp -rp ./help/ the_name_of_the_new_directory/ 4. If you want LaTeX hard copy of the on-line help files provided with difmap, check that you have the latex and dvi2ps commands installed on your machine, ensure that difmap is in your path, and type the following: cd doc ./makemanual This will create a LaTeX file (help.tex) and run latex on it to produce help.dvi. To print this type: dvi2ps help.dvi | lpr - 5. The only files that must be retained after building difmap, are the help files (in the directory that you chose to install them in). All other files can now be deleted if you wish to conserve space. You might want to keep the difmap2.3c.tar.Z file around. NOTE that the ./configure script and the ./makeall script can be run any number of times, but note that ./configure script re-builds the make files in each subdirectory, so changes to the make files will be lost. If for some reason you need to restart the installation from scratch, there is a script in the top level directory called "clean". To run it just type: ./clean This deletes object files, library files, make files etc. When it has finished you can go back to step 1 and re-start the installation process from scratch. RUNNING DIFMAP -------------- Make sure that the difmap executable is in your PATH (also type rehash if you are using csh or tcsh) and type: > difmap You should then see a message like: Caltech difference mapping program - version 2.3c (21 Mar 98) Copyright (c) 1993 California Institute of Technology. All Rights Reserved. Type 'help difmap' to list difference mapping commands and help topics. Started logfile: difmap.log on Sun Mar 21 15:53:12 1998 0> Where 0> is the difmap prompt. If you then type: 0> help difmap Difmap will list a set of general help topics, followed by a list of all difmap commands, each annotated with a 1-line description. Type help and the name of any of these commands to get further help. (Hint: type help observe to get started). To get out of difmap, type: 0> exit For a simple introduction to using Difmap, please read the Difmap Cookbook (written by Greg Taylor). If you have any problems, send email to me at the following address. Martin Shepherd (mcs@astro.caltech.edu)