Installation Instructions
=========================

Platform specific installation notes appear after the 
following generic instructions.

Standard Installation Instruction
---------------------------------

To build the qd library, follow the following steps.

  1. Run the configure script by typing

       ./configure

     The script will attempt to automatically detect various 
     system-dependent features used during compilation (such as 
     C++ / Fortran compiler characteristics and availability of 
     certain system headers).

     If you want to specify a particular C++ / Fortran-90 compiler 
     and their compiler flags, you can set them as environmental 
     variables before running configure.  For example:

       CXX=icc CXXFLAGS='-O2 -mp' FC=ifort FCFLAGS='-O2 -mp' ./configure

     Some variable of interests are

       CXX       C++ compiler to use
       CXXFLAGS  C++ compiler flags to use
       FC        Fortran 90 compiler
       FCFLAGS   Fortran 90 compiler flags to use
       FCLIBS    Fortran 90 libraries needed to to link with C++ code
       LDFLAGS   Linker flags

     For more build options, type "./configure --help".  In particular, 
     if you want to install to a custom path, do something like

       ./configure --prefix=/custom/path

  3. Type "make".  This will build the qd library.

  4. Optionally, one can build and run some simple test programs.
     To do this, type "make check".  Some programs run during this
     phase (especially qd_test and pslq_test in tests directory) is
     a good demonstration of how to use the qd library in C++.

     There are two other programs qd_timer and quadt_test that can be
     built inside tests directory using "make qd_timer" and "make 
     quadt_test".  The program qd_timer times the basic operations in 
     double-double and quad-double.  The program quadt_test is another
     demo program that computes quadratures of various functions.

  5. If you want to build some sample programs written in Fortran 90, 
     you can type "make fortran-demo".

  6. Type "make install" to install the quad-double library to
     the location specified (through --prefix option) to the configure 
     script (default is "/usr/local").


Platform Specific Notes
-----------------------

Cygwin   On Windows running Cygwin, you may need to specify CXX=g++, since
         otherwise the configure script may use CC, which is linked to 
         gcc (C compiler, not C++ compiler).  This is caused by the fact that
         most Windows filesystems is not case sensitive (cc and CC is the
         same file).