Installation and porting
========================

Installation
------------

Blitz++ uses GNU Autoconf, which handles rewriting Makefiles for various platforms and compilers.  It has greatly simplified installation and porting.  Many thanks for John W. Eaton and Brendan Kehoe for their help with this.

To install blitz, unpack the blitz-VERSION.tar.gz file (it will install into a subdirectory blitz-VERSION).  For example:

     [tveldhui@n2001:~] 32: ls -l blitz*.gz
     -rw-r--r--   1 tveldhui users      480953 Jun 23 15:20 blitz-0.5.tar.gz
     [tveldhui@n2001:~] 33: gunzip blitz-0.5.tar.gz
     [tveldhui@n2001:~] 34: tar xvf blitz-0.5.tar
     blitz-0.5/CHANGELOG
     blitz-0.5/COPYING
     blitz-0.5/INSTALL
     blitz-0.5/Makefile.in
     blitz-0.5/README
     blitz-0.5/THANKS
       .
       .

Then go into the main blitz directory, and type:

     ./configure CXX=[compiler]

where [compiler] is one of xlc++, icpc, xlC, cxx, aCC, CC, g++, KCC, pgCC or FCC.

You can also specify special command-line options for your compiler, using this syntax:

     ./configure CXX=g++ CXXFLAGS="-ftemplate-depth-50"

If you are interested in benchmarking, you may want to use the option --with-blas=... to specify the path where the blas library is found. Run the configure script with the option --help to see all the available options.

Once the configure script is done, you can do any of these things:

make lib
     Check the compiler and create libblitz.a.

make check-testsuite
     Make the blitz library plus build and run the testsuite.

make check-examples
     Make the blitz library plus build and run the examples.

make check-benchmarks
     Make the blitz library plus build and run the benchmarks.

make all
     Do all of the above.  This may take a long time.

make install
     Build the blitz library and documentation and install, along with the blitz header files, in prefix directory.

Building the benchmark programs requires both a Fortran 77 and Fortran 90 compiler.

The Blitz++ directory tree
--------------------------

The main Blitz++ directory contains these subdirectories:

blitz
     Blitz++ headers and source code files

random
     Random number generators

src
     Source code for libblitz.a

lib
     Location of libblitz.a

doc
     Documentation in HTML and PostScript

testsuite
     Testsuite programs

examples
     Example programs

benchmarks
     Benchmark programs

Porting Blitz++
---------------

If you want to try porting Blitz++ to a new compiler or platform, I suggest the following approach:

  * First check the Blitz++ web page to make sure you have the latest snapshot, and that someone hasn't already ported blitz to your platform.

  * Install autoconf (from e.g. ftp://prep.ai.mit.edu/pub/gnu) if you don't have it already.

  * Run the configure script with CXX=[compiler].  This will exercise your compiler to see what language features it supports.  If it doesn't have member templates and enum computations, just give up.  You may need to set CXXFLAGS to use compiler options that enable some language features.

  * Once you know what compiler options are needed, you can make these the default settings for your C++ compiler.  Make a backup of m4/ac_cxx_flags_preset.m4, and then edit the file to add an appropriate case for your compiler.  Invoke autoconf to regenerate the configure script.  Then try configure with your new preset flags.