Harminv installation

From AbInitio

Harminv is designed to run on any Unix-like system (GNU/Linux is fine), and uses a configure script to make it easy to install. However, you do need a couple of prerequisites:

BLAS

The first thing you must have on your system is a BLAS implementation. "BLAS" stands for "Basic Linear Algebra Subroutines," and is a standard interface for operations like matrix multiplication. It is designed as a building-block for other linear-algebra applications, and is used both directly by our code and in LAPACK (see below). By using it, we can take advantage of many highly-optimized implementations of these operations that have been written to the BLAS interface. (Note that you will need implementations of BLAS levels 1-3.)

You can find more BLAS information, as well as a basic implementation, on the BLAS Homepage. Once you get things working with the basic BLAS implementation, it might be a good idea to try and find a more optimized BLAS code for your hardware. Vendor-optimized BLAS implementations are available as part of the Intel MKL, HP CXML, IBM ESSL, SGI sgimath, and other libraries. Recently, there has also been work on self-optimizing BLAS implementations that can achieve performance competitive with vendor-tuned codes; see the ATLAS homepage. ATLAS works well, but it does take some time to compile.

Note that the generic BLAS does not come with a Makefile; compile it with something like:

mkdir blas && cd blas # the BLAS archive does not create its own directory
get http://www.netlib.org/blas/blas.tgz
gunzip blas.tgz
tar xf blas.tar
f77 -c -O3 *.f   # compile all of the .f files to produce .o files
ar rv libblas.a *.o    #  combine the .o files into a library
su -c "cp libblas.a /usr/local/lib"   # switch to root and install

(Replace -O3 with your favorite optimization options. On Linux, I use g77 -O3 -fomit-frame-pointer -funroll-loops, with -malign-double -mcpu=i686 on a Pentium II.) Note that MPB looks for the standard BLAS library with -lblas, so the library file should be called libblas.a and reside in a standard directory like /usr/local/lib. (See also below for the --with-blas=lib option to MPB's configure script, to manually specify a library location.)

LAPACK

LAPACK, the Linear Algebra PACKage, is a standard collection of routines, built on BLAS, for more-complicated (dense) linear algebra operations like matrix inversion and diagonalization. You can download LAPACK from the LAPACK Home Page.

Note that our software looks for LAPACK by linking with -llapack. This means that the library must be called liblapack.a and be installed in a standard directory like /usr/local/lib (alternatively, you can specify another directory via the LDFLAGS environment variable as described earlier). (See also below for the --with-lapack=lib option to our configure script, to manually specify a library location.)

Compiling Harminv Itself

Once you have those installed, you can compile and install harminv. harminv comes with a GNU-style configure script, so on Unix-like systems compilation is ideally just a matter of:

./configure
make

and then switching to root and running:

make install

By default, this installs under /usr/local, i.e. in /usr/local/bin etcetera. You can change this by passing the standard --prefix=dir option to configure. Other configure options can be found by running ./configure --help.

In order to compile, harminv requires either:

• An ANSI C compiler supporting complex numbers, as defined in the ANSI C99 standard (or a reasonable approximation thereof). For example, gcc-2.95 with GNU libc is fine.
• A C++ compiler supporting the complex standard template class.

The configure script looks for a C compiler with complex numbers first, and then, if that fails, for a C++ compiler. You can force it to use C++ by passing --with-cxx to configure.

If you need to, you can have further control over the configure script's behavior by setting enviroment variables, by passing VARIABLE=VALUE arguments to configure. This can be useful especially if you have libraries installed in nonstandard locations (e.g. in your home directory, if you are not a system administrator), to tell the compiler where to look. The most common variables to set are:

• CC: the C compiler command
• CFLAGS: the C compiler flags
• CXX: the C++ compiler command
• CXXFLAGS: the C++ compiler flags
• F77: the Fortran 77 compiler command. Important: if you have more than one Fortran compiler, use the same compiler here as you used for BLAS/LAPACK.
• FFLAGS: the Fortran 77 compiler flags
• CPPFLAGS: -Idir flags to tell the C compiler additional places to look for header files.
• LDFLAGS: -Ldir flags to tell the linker additional places to look for libraries.
• LIBS: additional libraries to link against.