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) 1992-2022 by the California Institute of Technology. Author: Martin C. Shepherd 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. The contents of the libtecla_src directory is copyright by the author, Martin Shepherd. See libtecla_src/LICENSE.TERMS for copyright details. If you are interested in using the tecla terminal-input library in your own programs please see libtecla_src/README. 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 2.5q was designed to compile on computers running various flavors of Unix, Linux and MacOS X. SHOPPING LIST ------------- To successfully install difmap you will need the following items: 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 ftp.astro.caltech.edu in directory /pub/pgplot/. Older versions of PGPLOT will not work with this version of Difmap. GETTING THE LATEST DISTRIBUTION OF DIFMAP VIA A WEB-BROWSER ----------------------------------------------------------- The latest version of difmap can be obtained from the following URL: http://astro.caltech.edu/~mcs/difmap/index.html In that directory you will find the latest difmap tar file, plus the difmap cookbook, which is a postscript file. GETTING THE LATEST DISTRIBUTION OF DIFMAP VIA ANONYMOUS FTP ----------------------------------------------------------- It can also be obtained from the previous anonymous FTP URL, ftp.astro.caltech.edu. Supply the word, anonymous, as your username and send your email address as the corresponding password. For example: % ftp ftp.astro.caltech.edu Name (ftp.astro.caltech.edu:mcs): anonymous 331 Please specify the password. Password: guest ftp> pass ftp> cd pub/difmap ftp> binary ftp> get difmap2.5q.tar.gz ftp> get cookbook.ps.gz ftp> quit UNPACKING DIFMAP FROM THE DOWNLOADED TAR FILE: ---------------------------------------------- Decide where you wish to unpack and compile difmap, place the compressed tar file that you just downloaded into that directory, then unpack the tar file as follows: tar xzf difmap2.5q.tar.gz This will place all of the files found in the tar file under a subdirectory called ./uvf_difmap_2.5q Move into this subdirectory. cd uvf_difmap_2.5q/ 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 modern PC running Linux, compiling it using the Gnu C compiler, gcc, you would type: ./configure linux-i486-gcc 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 runs 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. 3. Move the help files to the directory assigned to HELPDIR in the configure script. mkdir the_help_directory cp -rp ./help/ the_help_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 difmap executable (called difmap), and 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. NOTE that the ./configure script and the ./makeall script can be run any number of times, but note that the ./configure script re-builds the make files in each subdirectory, so this will overwrite any changes that you have made to the make files. 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, auto-generated 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 2.5q (3 Dec 2022) Copyright (c) 1993-2022 California Institute of Technology. All Rights Reserved. Type 'help difmap' to list difference mapping commands and help topics. Started logfile: difmap.log on Sat Dec 3 11:28:35 2022 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). Martin Shepherd (mcs.shepherd at gmail.com)