--- a
+++ b/m4/ax_lapack.m4
@@ -0,0 +1,131 @@
+# ===========================================================================
+#         http://www.gnu.org/software/autoconf-archive/ax_lapack.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_LAPACK([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
+#
+# DESCRIPTION
+#
+#   This macro looks for a library that implements the LAPACK linear-algebra
+#   interface (see http://www.netlib.org/lapack/). On success, it sets the
+#   LAPACK_LIBS output variable to hold the requisite library linkages.
+#
+#   To link with LAPACK, you should link with:
+#
+#     $LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS
+#
+#   in that order. BLAS_LIBS is the output variable of the AX_BLAS macro,
+#   called automatically. FLIBS is the output variable of the
+#   AC_F77_LIBRARY_LDFLAGS macro (called if necessary by AX_BLAS), and is
+#   sometimes necessary in order to link with F77 libraries. Users will also
+#   need to use AC_F77_DUMMY_MAIN (see the autoconf manual), for the same
+#   reason.
+#
+#   The user may also use --with-lapack=<lib> in order to use some specific
+#   LAPACK library <lib>. In order to link successfully, however, be aware
+#   that you will probably need to use the same Fortran compiler (which can
+#   be set via the F77 env. var.) as was used to compile the LAPACK and BLAS
+#   libraries.
+#
+#   ACTION-IF-FOUND is a list of shell commands to run if a LAPACK library
+#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
+#   is not found. If ACTION-IF-FOUND is not specified, the default action
+#   will define HAVE_LAPACK.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 7
+
+AU_ALIAS([ACX_LAPACK], [AX_LAPACK])
+AC_DEFUN([AX_LAPACK], [
+AC_REQUIRE([AX_BLAS])
+ax_lapack_ok=no
+
+AC_ARG_WITH(lapack,
+        [AS_HELP_STRING([--with-lapack=<lib>], [use LAPACK library <lib>])])
+case $with_lapack in
+        yes | "") ;;
+        no) ax_lapack_ok=disable ;;
+        -* | */* | *.a | *.so | *.so.* | *.o) LAPACK_LIBS="$with_lapack" ;;
+        *) LAPACK_LIBS="-l$with_lapack" ;;
+esac
+
+# Get fortran linker name of LAPACK function to check for.
+AC_F77_FUNC(cheev)
+
+# We cannot use LAPACK if BLAS is not found
+if test "x$ax_blas_ok" != xyes; then
+        ax_lapack_ok=noblas
+        LAPACK_LIBS=""
+fi
+
+# First, check LAPACK_LIBS environment variable
+if test "x$LAPACK_LIBS" != x; then
+        save_LIBS="$LIBS"; LIBS="$LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS"
+        AC_MSG_CHECKING([for $cheev in $LAPACK_LIBS])
+        AC_TRY_LINK_FUNC($cheev, [ax_lapack_ok=yes], [LAPACK_LIBS=""])
+        AC_MSG_RESULT($ax_lapack_ok)
+        LIBS="$save_LIBS"
+        if test $ax_lapack_ok = no; then
+                LAPACK_LIBS=""
+        fi
+fi
+
+# LAPACK linked to by default?  (is sometimes included in BLAS lib)
+if test $ax_lapack_ok = no; then
+        save_LIBS="$LIBS"; LIBS="$LIBS $BLAS_LIBS $FLIBS"
+        AC_CHECK_FUNC($cheev, [ax_lapack_ok=yes])
+        LIBS="$save_LIBS"
+fi
+
+# Generic LAPACK library?
+for lapack in lapack lapack_rs6k; do
+        if test $ax_lapack_ok = no; then
+                save_LIBS="$LIBS"; LIBS="$BLAS_LIBS $LIBS"
+                AC_CHECK_LIB($lapack, $cheev,
+                    [ax_lapack_ok=yes; LAPACK_LIBS="-l$lapack"], [], [$FLIBS])
+                LIBS="$save_LIBS"
+        fi
+done
+
+AC_SUBST(LAPACK_LIBS)
+
+# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
+if test x"$ax_lapack_ok" = xyes; then
+        ifelse([$1],,AC_DEFINE(HAVE_LAPACK,1,[Define if you have LAPACK library.]),[$1])
+        :
+else
+        ax_lapack_ok=no
+        $2
+fi
+])dnl AX_LAPACK