updated libquantum 1.1.0 source files

CHANGES

@@ -1,4 +1,7 @@
-libquantum 1.0.0:
+libquantum 1.1.0:
+	- Added exact diagonlization based on LAPACK
+	- Added flag in quantum_rk4 to preserve qureg (breaks backward 
+	  compatibility)
 	- Fixed quantum_gate1 to work properly with sorted regs
 	- Fixed several bugs in quantum_rk4a
 

Makefile.in

@@ -1,6 +1,6 @@
 # Makefile: Build libquantum
 # 
-# Copyright 2003-2005 Bjoern Butscher, Hendrik Weimer
+# Copyright 2003-2008 Bjoern Butscher, Hendrik Weimer
 #
 # This file is part of libquantum
 #
@@ -49,7 +49,7 @@ LIBTOOL=@LIBTOOL@
 # Flags passed to C compiler
 
 CFLAGS=@CFLAGS@
-LDFLAGS=-rpath $(LIBDIR) -version-info 6:1:3
+LDFLAGS=-rpath $(LIBDIR) -version-info 7:0:0
 
 # Dependencies
 
@@ -57,11 +57,11 @@ all:	libquantum.la
 
 libquantum.la: complex.lo measure.lo matrix.lo gates.lo qft.lo classic.lo \
 	qureg.lo decoherence.lo oaddn.lo omuln.lo expn.lo qec.lo version.lo \
-	objcode.lo density.lo error.lo qtime.lo Makefile
+	objcode.lo density.lo error.lo qtime.lo lapack.lo Makefile
 	$(LIBTOOL) --mode=link $(CC) $(LDFLAGS) -o libquantum.la complex.lo \
 	measure.lo matrix.lo gates.lo oaddn.lo omuln.lo expn.lo qft.lo \
 	classic.lo qureg.lo decoherence.lo qec.lo version.lo objcode.lo \
-	density.lo error.lo qtime.lo -lm
+	density.lo error.lo qtime.lo lapack.lo @LIBS@
 
 complex.lo: complex.c complex.h config.h Makefile
 	$(LIBTOOL) --mode=compile $(CC) $(CFLAGS) -c complex.c
@@ -120,6 +120,9 @@ error.lo: error.c error.h Makefile
 qtime.lo: qtime.c qtime.h qureg.h Makefile
 	$(LIBTOOL) --mode=compile $(CC) $(CFLAGS) -c qtime.c
 
+lapack.lo: lapack.c lapack.h matrix.h qureg.h config.h error.h Makefile
+	$(LIBTOOL) --mode=compile $(CC) $(CFLAGS) -c lapack.c
+
 # Autoconf stuff
 
 Makefile: config.status Makefile.in aclocal.m4 config.h.in types.h.in \

config.h.in

@@ -1,6 +1,6 @@
 /* config.h: configure settings
 
-   Copyright 2003-2005 Bjoern Butscher, Hendrik Weimer
+   Copyright 2003-2008 Bjoern Butscher, Hendrik Weimer
 
    This file is part of libquantum
 
@@ -91,4 +91,7 @@
 /* Define to 1 if you have GCC */
 #undef HAVE_GCC
 
+/* Define to 1 if you have LAPACK */
+#undef HAVE_LIBLAPACK
+
 #include "types.h"

configure

@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.61 for libquantum 1.0.0.
+# Generated by GNU Autoconf 2.61 for libquantum 1.1.0.
 #
 # Report bugs to <libquantum@libquantum.de>.
 #
@@ -724,8 +724,8 @@ SHELL=${CONFIG_SHELL-/bin/sh}
 # Identity of this package.
 PACKAGE_NAME='libquantum'
 PACKAGE_TARNAME='libquantum'
-PACKAGE_VERSION='1.0.0'
+PACKAGE_VERSION='1.1.0'
-PACKAGE_STRING='libquantum 1.0.0'
+PACKAGE_STRING='libquantum 1.1.0'
 PACKAGE_BUGREPORT='libquantum@libquantum.de'
 
 ac_unique_file="classic.c"
@@ -1346,7 +1346,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures libquantum 1.0.0 to adapt to many kinds of systems.
+\`configure' configures libquantum 1.1.0 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1411,7 +1411,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of libquantum 1.0.0:";;
+     short | recursive ) echo "Configuration of libquantum 1.1.0:";;
    esac
   cat <<\_ACEOF
 
@@ -1432,9 +1432,11 @@ Optional Packages:
   --with-pic              try to use only PIC/non-PIC objects [default=use
                           both]
   --with-tags[=TAGS]      include additional configurations [automatic]
-  --with-max-unsigned-type=ARG  integer type for quantum registers
+  --with-lapack        LAPACK support default=yes
-  --with-complex-type=ARG  type for complex numbers
+  --with-max-unsigned-type=ARG
-  --with-imaginary=ARG  name of the imaginary unit
+                          integer type for quantum registers
+  --with-complex-type=ARG type for complex numbers
+  --with-imaginary=ARG    name of the imaginary unit
 
 Some influential environment variables:
   CC          C compiler command
@@ -1510,7 +1512,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-libquantum configure 1.0.0
+libquantum configure 1.1.0
 generated by GNU Autoconf 2.61
 
 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
@@ -1524,7 +1526,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by libquantum $as_me 1.0.0, which was
+It was created by libquantum $as_me 1.1.0, which was
 generated by GNU Autoconf 2.61.  Invocation command line was
 
   $ $0 $@
@@ -3695,7 +3697,7 @@ ia64-*-hpux*)
   ;;
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 3698 "configure"' > conftest.$ac_ext
+  echo '#line 3700 "configure"' > conftest.$ac_ext
   if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
@@ -5414,11 +5416,11 @@ else
    -e 's:.*FLAGS}? :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:5417: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:5419: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:5421: \$? = $ac_status" >&5
+   echo "$as_me:5423: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings
@@ -5647,11 +5649,11 @@ else
    -e 's:.*FLAGS}? :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:5650: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:5652: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:5654: \$? = $ac_status" >&5
+   echo "$as_me:5656: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings
@@ -5707,11 +5709,11 @@ else
    -e 's:.*FLAGS}? :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:5710: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:5712: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:5714: \$? = $ac_status" >&5
+   echo "$as_me:5716: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -7867,7 +7869,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 7870 "configure"
+#line 7872 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -7965,7 +7967,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 7968 "configure"
+#line 7970 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -8790,6 +8792,158 @@ _ACEOF
 fi
 
 
+# Check whether --with-lapack was given.
+if test "${with_lapack+set}" = set; then
+  withval=$with_lapack; if test $withval = "yes"
+	then
+
+{ echo "$as_me:$LINENO: checking for cheev_ in -llapack" >&5
+echo $ECHO_N "checking for cheev_ in -llapack... $ECHO_C" >&6; }
+if test "${ac_cv_lib_lapack_cheev_+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-llapack  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char cheev_ ();
+int
+main ()
+{
+return cheev_ ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext &&
+       $as_test_x conftest$ac_exeext; then
+  ac_cv_lib_lapack_cheev_=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_cv_lib_lapack_cheev_=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_lib_lapack_cheev_" >&5
+echo "${ECHO_T}$ac_cv_lib_lapack_cheev_" >&6; }
+if test $ac_cv_lib_lapack_cheev_ = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBLAPACK 1
+_ACEOF
+
+  LIBS="-llapack $LIBS"
+
+fi
+
+	fi
+else
+
+{ echo "$as_me:$LINENO: checking for cheev_ in -llapack" >&5
+echo $ECHO_N "checking for cheev_ in -llapack... $ECHO_C" >&6; }
+if test "${ac_cv_lib_lapack_cheev_+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-llapack  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char cheev_ ();
+int
+main ()
+{
+return cheev_ ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext &&
+       $as_test_x conftest$ac_exeext; then
+  ac_cv_lib_lapack_cheev_=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_cv_lib_lapack_cheev_=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_lib_lapack_cheev_" >&5
+echo "${ECHO_T}$ac_cv_lib_lapack_cheev_" >&6; }
+if test $ac_cv_lib_lapack_cheev_ = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBLAPACK 1
+_ACEOF
+
+  LIBS="-llapack $LIBS"
+
+fi
+
+fi
+
+
+
 # Checks for header files.
 { echo "$as_me:$LINENO: checking for ANSI C header files" >&5
 echo $ECHO_N "checking for ANSI C header files... $ECHO_C" >&6; }
@@ -9700,6 +9854,9 @@ if test "${enable_profiling+set}" = set; then
 fi
 
 
+# Disable LAPACK check
+
+
 # Enable -Wall for gcc
 if test $CC = "gcc"
 then
@@ -10109,7 +10266,7 @@ exec 6>&1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by libquantum $as_me 1.0.0, which was
+This file was extended by libquantum $as_me 1.1.0, which was
 generated by GNU Autoconf 2.61.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -10158,7 +10315,7 @@ Report bugs to <bug-autoconf@gnu.org>."
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF
 ac_cs_version="\\
-libquantum config.status 1.0.0
+libquantum config.status 1.1.0
 configured by $0, generated by GNU Autoconf 2.61,
   with options \\"`echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"
 

configure.in

@@ -20,7 +20,7 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 # MA 02110-1301, USA
 
-AC_INIT([libquantum], [1.0.0], [libquantum@libquantum.de])
+AC_INIT([libquantum], [1.1.0], [libquantum@libquantum.de])
 AC_CONFIG_SRCDIR([classic.c])
 AC_CONFIG_HEADER([config.h])
 
@@ -34,6 +34,13 @@ AC_PROG_LIBTOOL
 
 # Checks for libraries.
 AC_CHECK_LIB([m], [sqrt])
+AC_ARG_WITH(lapack,
+	[  --with-lapack        LAPACK support [default=yes]],
+	[if test $withval = "yes"
+	then 
+	     AC_CHECK_LIB([lapack], [cheev_])
+	fi] , [AC_CHECK_LIB([lapack], [cheev_])])
+
 
 # Checks for header files.
 AC_HEADER_STDC
@@ -44,7 +51,8 @@ AC_C_INLINE
 
 # Check for 64-bit integer
 AC_ARG_WITH([max-unsigned-type], 
-	[  --with-max-unsigned-type=ARG  integer type for quantum registers], 
+	[  --with-max-unsigned-type=ARG
+                          integer type for quantum registers], 
 	[MU_TYPE=$withval], [MU_TYPE="none"
 	AC_CHECK_TYPE([uint_64t], [AC_DEFINE([MAX_UNSIGNED], [uint_64t]) 
 	MU_TYPE="uint_64t"])])
@@ -66,7 +74,7 @@ fi
 
 # Check for complex number type
 AC_ARG_WITH([complex-type],
-	[  --with-complex-type=ARG  type for complex numbers], 
+	[  --with-complex-type=ARG type for complex numbers], 
 	[CF_TYPE=$withval
 ], [CF_TYPE="none"
 	AC_CHECK_TYPE([float _Complex], [AC_DEFINE([COMPLEX_FLOAT], 
@@ -86,7 +94,7 @@ fi
 # Check for the imaginary unit
 AC_MSG_CHECKING([for the imaginary unit])
 AC_ARG_WITH([imaginary],
-	[  --with-imaginary=ARG  name of the imaginary unit], 
+	[  --with-imaginary=ARG    name of the imaginary unit], 
 	[I=$withval], [I="none"
 	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([$CF_TYPE z;], [z=I;])], 
 		[AC_DEFINE([IMAGINARY], [I], [Imaginary unit]) I="I"])
@@ -112,6 +120,9 @@ AC_ARG_ENABLE(profiling,
 	    then CFLAGS="$CFLAGS -pg -fprofile-arcs -ftest-coverage"
 	fi], [])
 
+# Disable LAPACK check
+
+
 # Enable -Wall for gcc
 if test $CC = "gcc"
 then

error.c

@@ -54,6 +54,12 @@ quantum_strerr(int errno)
       return "wrong matrix size";
     case QUANTUM_EHASHFULL:
       return "hash table full";
+    case QUANTUM_ENOLAPACK:
+      return "LAPACK support not compiled in";
+    case QUANTUM_ELAPACKARG:
+      return "wrong arguments supplied to LAPACK";
+    case QUANTUM_ELAPACKCHEEV:
+      return "LAPACK's CHEEV failed to converge";
     case QUANTUM_EMCMATRIX:
       return "single-column matrix expected";
     case QUANTUM_EOPCODE:

error.h

@@ -26,14 +26,17 @@
 #define __ERROR_H
 
 enum {
-  QUANTUM_SUCCESS   = 0,
+  QUANTUM_SUCCESS      = 0,
-  QUANTUM_FAILURE   = 1,
+  QUANTUM_FAILURE      = 1,
-  QUANTUM_ENOMEM    = 2,
+  QUANTUM_ENOMEM       = 2,
-  QUANTUM_EMLARGE   = 3,
+  QUANTUM_EMLARGE      = 3,
-  QUANTUM_EMSIZE    = 4,
+  QUANTUM_EMSIZE       = 4,
-  QUANTUM_EHASHFULL = 5,
+  QUANTUM_EHASHFULL    = 5,
-  QUANTUM_EMCMATRIX = 65536, /* internal errors start at 65536 */
+  QUANTUM_ENOLAPACK    = 32768, /* LAPACK errors start at 32768 */
-  QUANTUM_EOPCODE   = 65537
+  QUANTUM_ELAPACKARG   = 32769,
+  QUANTUM_ELAPACKCHEEV = 32770,
+  QUANTUM_EMCMATRIX    = 65536, /* internal errors start at 65536 */
+  QUANTUM_EOPCODE      = 65537
 };
 
 extern void *quantum_error_handler(void *f(int));

lapack.c

@@ -0,0 +1,147 @@
+/* lapack.c: LAPACK interface
+
+   Copyright 2008 Bjoern Butscher, Hendrik Weimer
+
+   This file is part of libquantum
+
+   libquantum 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.
+
+   libquantum 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 libquantum; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA
+
+*/
+
+#include <stdlib.h>
+
+#include "lapack.h"
+#include "matrix.h"
+#include "complex.h"
+#include "qureg.h"
+#include "error.h"
+#include "config.h"
+
+extern void cheev_(char *jobz, char *uplo, int *n, float _Complex *A, int *lda,
+		   float *w, float _Complex *work, int *lwork, float *rwork,
+		   int *info);
+
+void 
+quantum_diag_time(float t, quantum_reg *reg0, quantum_reg *regt, 
+		  quantum_reg *tmp1, quantum_reg *tmp2, quantum_matrix H, 
+		  float **w)
+{
+#ifdef HAVE_LIBLAPACK
+  char jobz = 'V';
+  char uplo = 'U';
+  int dim = H.cols;
+  COMPLEX_FLOAT *work;
+  int lwork = -1;
+  float rwork[3*dim-2];
+  int info;
+  int i;
+  void *p;
+  
+  if(tmp2->size != reg0->size)
+    {
+      /* perform diagonalization */
+
+      p = regt->node;
+      *regt = *reg0;
+      regt->node = realloc(p, regt->size*sizeof(quantum_reg_node));
+      for(i=0; i<reg0->size; i++)
+	regt->node[i].state = i;
+      
+      p = tmp1->node;
+      *tmp1 = *reg0;
+      tmp1->node = realloc(p, regt->size*sizeof(quantum_reg_node));
+      for(i=0; i<reg0->size; i++)
+	tmp1->node[i].state = i;
+
+      p = tmp2->node;
+      *tmp2 = *reg0;
+      tmp2->node = realloc(p, regt->size*sizeof(quantum_reg_node));
+      for(i=0; i<reg0->size; i++)
+	tmp2->node[i].state = i;
+
+      *w = malloc(dim*sizeof(float));
+
+      if(!*w)
+	quantum_error(QUANTUM_ENOMEM);
+
+      work = malloc(sizeof(COMPLEX_FLOAT));
+
+      if(!work)
+	quantum_error(QUANTUM_ENOMEM);
+
+      cheev_(&jobz, &uplo, &dim, H.t, &dim, *w, work, &lwork, rwork, &info);
+
+      if(info < 0)
+	quantum_error(QUANTUM_ELAPACKARG);
+
+      else if(info > 0)
+	quantum_error(QUANTUM_ELAPACKCHEEV);
+      
+      lwork = (int) work[0];
+      work = realloc(work, lwork*sizeof(COMPLEX_FLOAT));
+
+      if(!work)
+	quantum_error(QUANTUM_ENOMEM);
+
+      cheev_(&jobz, &uplo, &dim, H.t, &dim, *w, work, &lwork, rwork, &info);
+
+      if(info < 0)
+	quantum_error(QUANTUM_ELAPACKARG);
+
+      else if(info > 0)
+	quantum_error(QUANTUM_ELAPACKCHEEV);
+      
+      free(work);
+
+      quantum_mvmult(tmp1, H, reg0);
+
+      quantum_adjoint(&H);
+    }
+
+  if(tmp1->size != reg0->size)
+    {
+      p = regt->node;
+      *regt = *reg0;
+      regt->node = realloc(p, regt->size*sizeof(quantum_reg_node));
+      for(i=0; i<reg0->size; i++)
+	regt->node[i].state = i;
+
+      p = tmp1->node;
+      *tmp1 = *reg0;
+      tmp1->node = realloc(p, regt->size*sizeof(quantum_reg_node));
+      for(i=0; i<reg0->size; i++)
+	tmp1->node[i].state = i;
+
+      quantum_adjoint(&H);
+      
+      quantum_mvmult(tmp1, H, reg0);
+
+      quantum_adjoint(&H);
+    }
+
+  for(i=0; i<dim; i++)
+    tmp2->node[i].amplitude = quantum_cexp(-(*w)[i]*t)*tmp1->node[i].amplitude;
+
+  quantum_mvmult(regt, H, tmp2);
+
+#else
+  quantum_error(QUANTUM_ENOLAPACK);
+
+#endif /* HAVE_LIBLAPACK */
+  
+}
+
+

lapack.h

@@ -0,0 +1,36 @@
+/* time.c: Declarations for lapack.h
+
+   Copyright 2006 Bjoern Butscher, Hendrik Weimer
+
+   This file is part of libquantum
+
+   libquantum 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.
+
+   libquantum 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 libquantum; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA
+
+*/
+
+#ifndef __LAPACK_H
+
+#define __LAPACK_H
+
+#include "config.h"
+#include "matrix.h"
+#include "qureg.h"
+
+extern void quantum_diag_time(float t, quantum_reg *reg0, quantum_reg *regt, 
+			      quantum_reg *tmp1, quantum_reg *tmp2, 
+			      quantum_matrix H, float **w);
+
+#endif

matrix.c

@@ -135,3 +135,23 @@ quantum_matrix quantum_mmult(quantum_matrix A, quantum_matrix B)
   return C;
 }
 
+/* Compute the adjoint of a matrix */
+
+void 
+quantum_adjoint(quantum_matrix *m)
+{
+  int i, j;
+  COMPLEX_FLOAT tmp;
+  quantum_matrix A = *m;
+
+  for(i=0; i<m->cols; i++)
+    {
+      for(j=0;j<i;j++)
+	{
+	  tmp = M(A, i, j);
+	  M(A, i, j) = quantum_conj(M(A, j, i));
+	  M(A, j, i) = quantum_conj(tmp);
+	}
+    }
+}
+

matrix.h

@@ -46,5 +46,6 @@ extern void quantum_delete_matrix(quantum_matrix *m);
 extern void quantum_print_matrix(quantum_matrix m);
 
 extern quantum_matrix quantum_mmult(quantum_matrix A, quantum_matrix B);
+extern void quantum_adjoint(quantum_matrix *m);
 
 #endif

qtime.c

@@ -34,7 +34,7 @@
 
 void
 quantum_rk4(quantum_reg *reg, double t, double dt, 
-	    quantum_reg H(MAX_UNSIGNED, double))
+	    quantum_reg H(MAX_UNSIGNED, double), int flags)
 {
   quantum_reg k, out, tmp;
   double r = 0;
@@ -49,7 +49,7 @@ quantum_rk4(quantum_reg *reg, double t, double dt,
   reg->hashw = 0;
 
   /* k1 */
-  k = quantum_matrix_qureg(H, t, reg);
+  k = quantum_matrix_qureg(H, t, reg, flags);
   quantum_scalar_qureg(-IMAGINARY*dt/2.0, &k);
   tmp = quantum_vectoradd(reg, &k);
   quantum_scalar_qureg(1.0/3.0, &k);
@@ -57,7 +57,7 @@ quantum_rk4(quantum_reg *reg, double t, double dt,
   quantum_delete_qureg(&k);
 
   /* k2 */
-  k = quantum_matrix_qureg(H, t+dt/2.0, &tmp);
+  k = quantum_matrix_qureg(H, t+dt/2.0, &tmp, flags);
   quantum_delete_qureg(&tmp);
   quantum_scalar_qureg(-IMAGINARY*dt/2.0, &k);
   tmp = quantum_vectoradd(reg, &k);
@@ -66,7 +66,7 @@ quantum_rk4(quantum_reg *reg, double t, double dt,
   quantum_delete_qureg(&k);
 
   /* k3 */
-  k = quantum_matrix_qureg(H, t+dt/2.0, &tmp);
+  k = quantum_matrix_qureg(H, t+dt/2.0, &tmp, flags);
   quantum_delete_qureg(&tmp);
   quantum_scalar_qureg(-IMAGINARY*dt, &k);
   tmp = quantum_vectoradd(reg, &k);
@@ -75,7 +75,7 @@ quantum_rk4(quantum_reg *reg, double t, double dt,
   quantum_delete_qureg(&k);
 
   /* k4 */
-  k = quantum_matrix_qureg(H, t+dt, &tmp);
+  k = quantum_matrix_qureg(H, t+dt, &tmp, flags);
   quantum_delete_qureg(&tmp);
   quantum_scalar_qureg(-IMAGINARY*dt/6.0, &k);
   quantum_vectoradd_inplace(&out, &k);
@@ -103,7 +103,7 @@ quantum_rk4(quantum_reg *reg, double t, double dt,
 
 double
 quantum_rk4a(quantum_reg *reg, double t, double *dt, double epsilon, 
-	     quantum_reg H(MAX_UNSIGNED, double))
+	     quantum_reg H(MAX_UNSIGNED, double), int flags)
 {
   quantum_reg reg2, old;
   double delta, r, dtused;
@@ -122,9 +122,9 @@ quantum_rk4a(quantum_reg *reg, double t, double *dt, double epsilon,
 
   do
     {
-      quantum_rk4(reg, t, *dt, H);
+      quantum_rk4(reg, t, *dt, H, flags);
-      quantum_rk4(&reg2, t, *dt/2.0, H);
+      quantum_rk4(&reg2, t, *dt/2.0, H, flags);
-      quantum_rk4(&reg2, t, *dt/2.0, H);
+      quantum_rk4(&reg2, t+*dt/2.0, *dt/2.0, H, flags);
 
       delta = 0;
 

qtime.h

@@ -29,9 +29,9 @@
 #include "config.h"
 
 extern void quantum_rk4(quantum_reg *reg, double t, double dt, 
-			quantum_reg H(MAX_UNSIGNED, double));
+			quantum_reg H(MAX_UNSIGNED, double), int flags);
 extern double quantum_rk4a(quantum_reg *reg, double t, double *dt, 
 			   double epsilon, 
-			   quantum_reg H(MAX_UNSIGNED, double));
+			   quantum_reg H(MAX_UNSIGNED, double), int flags);
 
 #endif

quantum.h.in

@@ -1,6 +1,6 @@
 /* quantum.h: Header file for libquantum
 
-   Copyright 2003-2007 Bjoern Butscher, Hendrik Weimer
+   Copyright 2003-2008 Bjoern Butscher, Hendrik Weimer
 
    This file is part of libquantum
 
@@ -138,7 +138,7 @@ extern COMPLEX_FLOAT quantum_dot_product(quantum_reg *reg1, quantum_reg *reg2);
 extern quantum_reg quantum_vectoradd(quantum_reg *reg1, quantum_reg *reg2);
 extern void quantum_vectoradd_inplace(quantum_reg *reg1, quantum_reg *reg2);
 extern quantum_reg quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double),
-					double t, quantum_reg *reg);
+					double t, quantum_reg *reg, int flags);
 extern void quantum_scalar_qureg(COMPLEX_FLOAT r, quantum_reg *reg);
 extern void quantum_print_timeop(int width, void f(quantum_reg *));
 
@@ -166,9 +166,13 @@ extern const char *quantum_strerr(int errno);
 extern void quantum_error(int errno);
 
 extern void quantum_rk4(quantum_reg *reg, double t, double dt, 
-			quantum_reg H(MAX_UNSIGNED, double));
+			quantum_reg H(MAX_UNSIGNED, double), int flags);
 extern double quantum_rk4a(quantum_reg *reg, double t, double *dt, 
 			   double epsilon, 
-			   quantum_reg H(MAX_UNSIGNED, double));
+			   quantum_reg H(MAX_UNSIGNED, double), int flags);
+
+extern void quantum_diag_time(float t, quantum_reg *reg0, quantum_reg *regt, 
+			      quantum_reg *tmp1, quantum_reg *tmp2, 
+			      quantum_matrix H, float **w);
 
 #endif

qureg.c

@@ -333,7 +333,7 @@ quantum_kronecker(quantum_reg *reg1, quantum_reg *reg2)
   
   reg.width = reg1->width+reg2->width;
   reg.size = reg1->size*reg2->size;
-  reg.hashw = reg.width+2;
+  reg.hashw = reg.width + 2;
 
 
   /* allocate memory for the new basis states */
@@ -605,7 +605,7 @@ quantum_vectoradd_inplace(quantum_reg *reg1, quantum_reg *reg2)
 
 quantum_reg
 quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double), double t,
-		     quantum_reg *reg)
+		     quantum_reg *reg, int flags)
 {
   MAX_UNSIGNED i;
   quantum_reg reg2;
@@ -627,7 +627,8 @@ quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double), double t,
       reg2.node[i].state = i;
       tmp = A(i, t);
       reg2.node[i].amplitude = quantum_dot_product_noconj(&tmp, reg);
-      quantum_delete_qureg(&tmp);
+      if(!(flags & 1))
+	quantum_delete_qureg(&tmp);
     }
   
  
@@ -635,6 +636,22 @@ quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double), double t,
 
 }
 
+/* Matrix-vector multiplication using a quantum_matrix */
+
+void 
+quantum_mvmult(quantum_reg *y, quantum_matrix A, quantum_reg *x)
+{
+  int i, j;
+
+  for(i=0; i<A.cols; i++)
+    {
+      y->node[i].amplitude = 0;
+      for(j=0; j<A.cols; j++)
+	y->node[i].amplitude += M(A, j, i)*x->node[j].amplitude;
+    }
+} 
+
+
 /* Scalar multiplication of a quantum register. This is a purely
    mathematical operation without any physical meaning, so only use it
    if you know what you are doing. */

qureg.h

@@ -79,8 +79,9 @@ extern COMPLEX_FLOAT quantum_dot_product(quantum_reg *reg1, quantum_reg *reg2);
 extern quantum_reg quantum_vectoradd(quantum_reg *reg1, quantum_reg *reg2);
 extern void quantum_vectoradd_inplace(quantum_reg *reg1, quantum_reg *reg2);
 extern quantum_reg quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double),
-					double t, quantum_reg *reg);
+					double t, quantum_reg *reg, int flags);
 extern void quantum_scalar_qureg(COMPLEX_FLOAT r, quantum_reg *reg);
+extern void quantum_mvmult(quantum_reg *y, quantum_matrix A, quantum_reg *x);
 
 extern void quantum_print_timeop(int width, void f(quantum_reg *));