AC_DEFUN([LX_CHECK_CPLEX],

 [

   AC_ARG_WITH([cplex],

 AS_HELP_STRING([--with-cplex@<:@=PREFIX@:>@], [search for CPLEX under PREFIX or under the default search paths if PREFIX is not given @<:@default@:>@])

 AS_HELP_STRING([--without-cplex], [disable checking for CPLEX]),

               [], [with_cplex=yes])

   AC_ARG_WITH([cplex-includedir],

 AS_HELP_STRING([--with-cplex-includedir=DIR], [search for CPLEX headers in DIR]),

               [], [with_cplex_includedir=no])

   AC_ARG_WITH([cplex-libdir],

 AS_HELP_STRING([--with-cplex-libdir=DIR], [search for CPLEX libraries in DIR]),

               [], [with_cplex_libdir=no])

   lx_cplex_found=no

   if test x"$with_cplex" != x"no"; then

     AC_MSG_CHECKING([for CPLEX])

     if test x"$with_cplex_includedir" != x"no"; then

       CPLEX_CFLAGS="-I$with_cplex_includedir"

     elif test x"$with_cplex" != x"yes"; then

       CPLEX_CFLAGS="-I$with_cplex/include"

     elif test x"$CPLEX_INCLUDEDIR" != x; then

       CPLEX_CFLAGS="-I$CPLEX_INCLUDEDIR"

     fi

     if test x"$with_cplex_libdir" != x"no"; then

       CPLEX_LDFLAGS="-L$with_cplex_libdir"

     elif test x"$with_cplex" != x"yes"; then

       CPLEX_LDFLAGS="-L$with_cplex/lib"

     elif test x"$CPLEX_LIBDIR" != x; then

       CPLEX_LDFLAGS="-L$CPLEX_LIBDIR"

     fi

     CPLEX_LIBS="-lcplex -lm -lpthread"

     lx_save_cxxflags="$CXXFLAGS"

     lx_save_ldflags="$LDFLAGS"

     lx_save_libs="$LIBS"

     CXXFLAGS="$CPLEX_CFLAGS"

     LDFLAGS="$CPLEX_LDFLAGS"

     LIBS="$CPLEX_LIBS"

     lx_cplex_test_prog='

       extern "C" {

       #include <ilcplex/cplex.h>

       }

       int main(int argc, char* argv[])

       {

         CPXENVptr env = NULL;

         return 0;

       }'

     AC_LANG_PUSH(C++)

     AC_LINK_IFELSE([$lx_cplex_test_prog], [lx_cplex_found=yes], [lx_cplex_found=no])

     AC_LANG_POP(C++)

     CXXFLAGS="$lx_save_cxxflags"

     LDFLAGS="$lx_save_ldflags"

     LIBS="$lx_save_libs"

     if test x"$lx_cplex_found" = x"yes"; then

       AC_DEFINE([HAVE_CPLEX], [1], [Define to 1 if you have CPLEX.])

       AC_MSG_RESULT([yes])

     else

       CPLEX_CFLAGS=""

       CPLEX_LDFLAGS=""

       CPLEX_LIBS=""

       AC_MSG_RESULT([no])

     fi

   fi

   CPLEX_LIBS="$CPLEX_LDFLAGS $CPLEX_LIBS"

   AC_SUBST(CPLEX_CFLAGS)

   AC_SUBST(CPLEX_LIBS)

   AM_CONDITIONAL([HAVE_CPLEX], [test x"$lx_cplex_found" = x"yes"])

 ])