Link to the source code for this example:
Open subdomains_ex1 in new tab.The console output of the program:
CXX example_dbg-subdomains_ex1.o
CXXLD example-dbg
***************************************************************
* Running Example subdomains_ex1:
* example-opt -d 1 -n 40
***************************************************************
Running /Users/petejw/projects/libmesh_git/build/examples/subdomains/subdomains_ex1/.libs/example-opt -d 1 -n 40
Mesh Information:
elem_dimensions()={1}
spatial_dimension()=1
n_nodes()=43
n_local_nodes()=43
n_elem()=44
n_local_elem()=44
n_active_elem()=42
n_subdomains()=1
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
EquationSystems
n_systems()=1
System #0, "Poisson"
Type "LinearImplicit"
Variables="u"
Finite Element Types="LAGRANGE", "JACOBI_20_00"
Infinite Element Mapping="CARTESIAN"
Approximation Orders="FIRST", "THIRD"
n_dofs()=43
n_local_dofs()=43
n_constrained_dofs()=0
n_local_constrained_dofs()=0
n_vectors()=1
n_matrices()=1
DofMap Sparsity
Average On-Processor Bandwidth <= 2.95349
Average Off-Processor Bandwidth <= 0
Maximum On-Processor Bandwidth <= 3
Maximum Off-Processor Bandwidth <= 0
DofMap Constraints
Number of DoF Constraints = 0
Mesh Information:
elem_dimensions()={1}
spatial_dimension()=1
n_nodes()=43
n_local_nodes()=43
n_elem()=44
n_local_elem()=44
n_active_elem()=42
n_subdomains()=2
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
-------------------------------------------------------------------------------------------------------------------
| Time: Wed Apr 13 10:45:21 2016 |
| OS: Darwin |
| HostName: peterson-laptop.local |
| OS Release: 15.0.0 |
| OS Version: Darwin Kernel Version 15.0.0: Sat Sep 19 15:53:46 PDT 2015; root:xnu-3247.10.11~1/RELEASE_X86_64 |
| Machine: x86_64 |
| Username: petejw |
| Configuration: ../configure 'INSTALL=/usr/bin/install -C' |
| '--with-methods=opt dbg' |
| '--prefix=/Users/petejw/projects/libmesh_git/installed' |
| '--enable-perflog' |
| '--enable-tracefiles' |
| '--disable-blocked-storage' |
| '--enable-default-comm-world' |
| '--enable-tecio' |
| '--enable-unique-ptr' |
| '--enable-ifem' |
| 'PETSC_DIR=/opt/moose/petsc/mpich_petsc-3.6.1/clang-opt-superlu' |
| 'SLEPC_DIR=/opt/petejw/slepc/3.6.1' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| '--disable-netcdf-4' |
| '--disable-testsets' |
| 'CXX=mpicxx' |
| 'CC=mpicc' |
| 'F77=mpif77' |
| 'FC=mpif90' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
-------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
| Matrix Assembly Performance: Alive time=0.000726, Active time=0.000175 |
------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|------------------------------------------------------------------------------------------------------------|
| |
| BCs 34 0.0000 0.000001 0.0000 0.000001 18.86 18.86 |
| Fe 34 0.0000 0.000001 0.0000 0.000001 9.71 9.71 |
| Ke 34 0.0000 0.000000 0.0000 0.000000 3.43 3.43 |
| elem init 34 0.0001 0.000003 0.0001 0.000003 58.86 58.86 |
| matrix insertion 34 0.0000 0.000000 0.0000 0.000000 9.14 9.14 |
------------------------------------------------------------------------------------------------------------
| Totals: 170 0.0002 100.00 |
------------------------------------------------------------------------------------------------------------
-----------------------------------------------------------------------------------------------------------------
| libMesh Performance: Alive time=0.009274, Active time=0.001939 |
-----------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|-----------------------------------------------------------------------------------------------------------------|
| |
| |
| DofMap |
| add_neighbors_to_send_list() 1 0.0000 0.000020 0.0000 0.000020 1.03 1.03 |
| build_sparsity() 1 0.0001 0.000084 0.0001 0.000094 4.33 4.85 |
| create_dof_constraints() 1 0.0000 0.000002 0.0000 0.000002 0.10 0.10 |
| distribute_dofs() 1 0.0000 0.000044 0.0001 0.000120 2.27 6.19 |
| dof_indices() 152 0.0000 0.000000 0.0000 0.000000 1.55 1.55 |
| prepare_send_list() 2 0.0000 0.000000 0.0000 0.000000 0.05 0.05 |
| reinit() 1 0.0001 0.000075 0.0001 0.000075 3.87 3.87 |
| |
| EquationSystems |
| build_solution_vector() 1 0.0001 0.000071 0.0001 0.000083 3.66 4.28 |
| |
| FE |
| compute_shape_functions() 36 0.0000 0.000000 0.0000 0.000000 0.72 0.72 |
| init_shape_functions() 3 0.0000 0.000002 0.0000 0.000002 0.26 0.26 |
| |
| FEMap |
| compute_affine_map() 36 0.0000 0.000000 0.0000 0.000000 0.67 0.67 |
| compute_face_map() 2 0.0000 0.000001 0.0000 0.000001 0.10 0.10 |
| init_face_shape_functions() 1 0.0000 0.000001 0.0000 0.000001 0.05 0.05 |
| init_reference_to_physical_map() 3 0.0000 0.000002 0.0000 0.000002 0.26 0.26 |
| |
| GnuPlotIO |
| write_nodal_data() 1 0.0003 0.000273 0.0003 0.000273 14.08 14.08 |
| |
| Mesh |
| find_neighbors() 2 0.0002 0.000077 0.0002 0.000077 7.94 7.94 |
| renumber_nodes_and_elem() 4 0.0000 0.000001 0.0000 0.000001 0.15 0.15 |
| |
| MeshOutput |
| write_equation_systems() 1 0.0000 0.000016 0.0004 0.000372 0.83 19.19 |
| |
| MeshRefinement |
| _refine_elements() 1 0.0000 0.000014 0.0000 0.000036 0.72 1.86 |
| add_node() 8 0.0000 0.000003 0.0000 0.000003 1.03 1.03 |
| make_flags_parallel_consistent() 1 0.0000 0.000014 0.0000 0.000014 0.72 0.72 |
| make_refinement_compatible() 1 0.0000 0.000007 0.0000 0.000007 0.36 0.36 |
| |
| MeshTools::Generation |
| build_cube() 1 0.0000 0.000042 0.0000 0.000042 2.17 2.17 |
| |
| Parallel |
| allgather() 1 0.0000 0.000001 0.0000 0.000001 0.05 0.05 |
| |
| Partitioner |
| single_partition() 2 0.0000 0.000004 0.0000 0.000004 0.46 0.46 |
| |
| PetscLinearSolver |
| solve() 1 0.0003 0.000291 0.0003 0.000291 15.01 15.01 |
| |
| System |
| assemble() 1 0.0007 0.000724 0.0008 0.000790 37.34 40.74 |
| |
| TopologyMap |
| init() 1 0.0000 0.000004 0.0000 0.000004 0.21 0.21 |
-----------------------------------------------------------------------------------------------------------------
| Totals: 267 0.0019 100.00 |
-----------------------------------------------------------------------------------------------------------------
***************************************************************
* Done Running Example subdomains_ex1:
* example-opt -d 1 -n 40
***************************************************************
***************************************************************
* Running Example subdomains_ex1:
* example-opt -d 2 -n 30
***************************************************************
Running /Users/petejw/projects/libmesh_git/build/examples/subdomains/subdomains_ex1/.libs/example-opt -d 2 -n 30
Mesh Information:
elem_dimensions()={2}
spatial_dimension()=2
n_nodes()=1329
n_local_nodes()=1329
n_elem()=1268
n_local_elem()=1268
n_active_elem()=1176
n_subdomains()=1
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
EquationSystems
n_systems()=1
System #0, "Poisson"
Type "LinearImplicit"
Variables="u"
Finite Element Types="LAGRANGE", "JACOBI_20_00"
Infinite Element Mapping="CARTESIAN"
Approximation Orders="FIRST", "THIRD"
n_dofs()=1329
n_local_dofs()=1329
n_constrained_dofs()=184
n_local_constrained_dofs()=184
n_vectors()=1
n_matrices()=1
DofMap Sparsity
Average On-Processor Bandwidth <= 9.2167
Average Off-Processor Bandwidth <= 0
Maximum On-Processor Bandwidth <= 15
Maximum Off-Processor Bandwidth <= 0
DofMap Constraints
Number of DoF Constraints = 184
Average DoF Constraint Length= 2
Mesh Information:
elem_dimensions()={2}
spatial_dimension()=2
n_nodes()=1329
n_local_nodes()=1329
n_elem()=1268
n_local_elem()=1268
n_active_elem()=1176
n_subdomains()=2
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
-------------------------------------------------------------------------------------------------------------------
| Time: Wed Apr 13 10:45:21 2016 |
| OS: Darwin |
| HostName: peterson-laptop.local |
| OS Release: 15.0.0 |
| OS Version: Darwin Kernel Version 15.0.0: Sat Sep 19 15:53:46 PDT 2015; root:xnu-3247.10.11~1/RELEASE_X86_64 |
| Machine: x86_64 |
| Username: petejw |
| Configuration: ../configure 'INSTALL=/usr/bin/install -C' |
| '--with-methods=opt dbg' |
| '--prefix=/Users/petejw/projects/libmesh_git/installed' |
| '--enable-perflog' |
| '--enable-tracefiles' |
| '--disable-blocked-storage' |
| '--enable-default-comm-world' |
| '--enable-tecio' |
| '--enable-unique-ptr' |
| '--enable-ifem' |
| 'PETSC_DIR=/opt/moose/petsc/mpich_petsc-3.6.1/clang-opt-superlu' |
| 'SLEPC_DIR=/opt/petejw/slepc/3.6.1' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| '--disable-netcdf-4' |
| '--disable-testsets' |
| 'CXX=mpicxx' |
| 'CC=mpicc' |
| 'F77=mpif77' |
| 'FC=mpif90' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
-------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
| Matrix Assembly Performance: Alive time=0.006794, Active time=0.004704 |
------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|------------------------------------------------------------------------------------------------------------|
| |
| BCs 628 0.0014 0.000002 0.0014 0.000002 29.63 29.63 |
| Fe 628 0.0011 0.000002 0.0011 0.000002 23.00 23.00 |
| Ke 628 0.0002 0.000000 0.0002 0.000000 4.87 4.87 |
| elem init 628 0.0017 0.000003 0.0017 0.000003 36.97 36.97 |
| matrix insertion 628 0.0003 0.000000 0.0003 0.000000 5.53 5.53 |
------------------------------------------------------------------------------------------------------------
| Totals: 3140 0.0047 100.00 |
------------------------------------------------------------------------------------------------------------
-----------------------------------------------------------------------------------------------------------------
| libMesh Performance: Alive time=0.030913, Active time=0.023643 |
-----------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|-----------------------------------------------------------------------------------------------------------------|
| |
| |
| DofMap |
| add_neighbors_to_send_list() 1 0.0002 0.000186 0.0002 0.000186 0.79 0.79 |
| build_constraint_matrix() 628 0.0003 0.000000 0.0003 0.000000 1.32 1.32 |
| build_sparsity() 1 0.0016 0.001615 0.0019 0.001862 6.83 7.88 |
| cnstrn_elem_mat_vec() 628 0.0002 0.000000 0.0002 0.000000 0.99 0.99 |
| create_dof_constraints() 1 0.0005 0.000503 0.0007 0.000676 2.13 2.86 |
| distribute_dofs() 1 0.0002 0.000192 0.0011 0.001057 0.81 4.47 |
| dof_indices() 5520 0.0008 0.000000 0.0008 0.000000 3.46 3.46 |
| prepare_send_list() 2 0.0000 0.000000 0.0000 0.000000 0.00 0.00 |
| reinit() 1 0.0009 0.000865 0.0009 0.000865 3.66 3.66 |
| |
| EquationSystems |
| build_solution_vector() 2 0.0012 0.000585 0.0018 0.000880 4.95 7.45 |
| |
| ExodusII_IO |
| write_nodal_data() 1 0.0019 0.001852 0.0019 0.001852 7.83 7.83 |
| |
| FE |
| compute_shape_functions() 828 0.0007 0.000001 0.0007 0.000001 2.89 2.89 |
| init_shape_functions() 201 0.0000 0.000000 0.0000 0.000000 0.10 0.10 |
| inverse_map() 784 0.0003 0.000000 0.0003 0.000000 1.11 1.11 |
| |
| FEMap |
| compute_affine_map() 828 0.0004 0.000001 0.0004 0.000001 1.84 1.84 |
| compute_face_map() 200 0.0002 0.000001 0.0005 0.000002 0.85 2.08 |
| init_face_shape_functions() 1 0.0000 0.000002 0.0000 0.000002 0.01 0.01 |
| init_reference_to_physical_map() 201 0.0002 0.000001 0.0002 0.000001 0.70 0.70 |
| |
| GMVIO |
| write_nodal_data() 1 0.0041 0.004141 0.0041 0.004141 17.51 17.51 |
| |
| Mesh |
| find_neighbors() 2 0.0033 0.001646 0.0033 0.001646 13.92 13.92 |
| renumber_nodes_and_elem() 4 0.0001 0.000015 0.0001 0.000015 0.26 0.26 |
| |
| MeshOutput |
| write_equation_systems() 2 0.0000 0.000014 0.0078 0.003891 0.12 32.91 |
| |
| MeshRefinement |
| _refine_elements() 1 0.0005 0.000452 0.0009 0.000913 1.91 3.86 |
| add_node() 1472 0.0003 0.000000 0.0003 0.000000 1.44 1.44 |
| make_flags_parallel_consistent() 1 0.0000 0.000045 0.0000 0.000045 0.19 0.19 |
| make_refinement_compatible() 1 0.0000 0.000018 0.0000 0.000018 0.08 0.08 |
| |
| MeshTools::Generation |
| build_cube() 1 0.0003 0.000256 0.0003 0.000256 1.08 1.08 |
| |
| Parallel |
| allgather() 1 0.0000 0.000000 0.0000 0.000000 0.00 0.00 |
| |
| Partitioner |
| single_partition() 2 0.0001 0.000028 0.0001 0.000028 0.24 0.24 |
| |
| PetscLinearSolver |
| solve() 1 0.0013 0.001342 0.0013 0.001342 5.68 5.68 |
| |
| System |
| assemble() 1 0.0041 0.004076 0.0068 0.006844 17.24 28.95 |
| |
| TopologyMap |
| init() 1 0.0000 0.000013 0.0000 0.000013 0.05 0.05 |
-----------------------------------------------------------------------------------------------------------------
| Totals: 11320 0.0236 100.00 |
-----------------------------------------------------------------------------------------------------------------
***************************************************************
* Done Running Example subdomains_ex1:
* example-opt -d 2 -n 30
***************************************************************
***************************************************************
* Running Example subdomains_ex1:
* example-opt -d 3 -n 15
***************************************************************
Running /Users/petejw/projects/libmesh_git/build/examples/subdomains/subdomains_ex1/.libs/example-opt -d 3 -n 15
Mesh Information:
elem_dimensions()={3}
spatial_dimension()=3
n_nodes()=10854
n_local_nodes()=10854
n_elem()=8767
n_local_elem()=8767
n_active_elem()=8093
n_subdomains()=1
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
EquationSystems
n_systems()=1
System #0, "Poisson"
Type "LinearImplicit"
Variables="u"
Finite Element Types="LAGRANGE", "JACOBI_20_00"
Infinite Element Mapping="CARTESIAN"
Approximation Orders="FIRST", "THIRD"
n_dofs()=10854
n_local_dofs()=10854
n_constrained_dofs()=4068
n_local_constrained_dofs()=4068
n_vectors()=1
n_matrices()=1
DofMap Sparsity
Average On-Processor Bandwidth <= 29.7157
Average Off-Processor Bandwidth <= 0
Maximum On-Processor Bandwidth <= 78
Maximum Off-Processor Bandwidth <= 0
DofMap Constraints
Number of DoF Constraints = 4068
Average DoF Constraint Length= 2.66667
Mesh Information:
elem_dimensions()={3}
spatial_dimension()=3
n_nodes()=10854
n_local_nodes()=10854
n_elem()=8767
n_local_elem()=8767
n_active_elem()=8093
n_subdomains()=2
n_partitions()=1
n_processors()=1
n_threads()=1
processor_id()=0
-------------------------------------------------------------------------------------------------------------------
| Time: Wed Apr 13 10:45:21 2016 |
| OS: Darwin |
| HostName: peterson-laptop.local |
| OS Release: 15.0.0 |
| OS Version: Darwin Kernel Version 15.0.0: Sat Sep 19 15:53:46 PDT 2015; root:xnu-3247.10.11~1/RELEASE_X86_64 |
| Machine: x86_64 |
| Username: petejw |
| Configuration: ../configure 'INSTALL=/usr/bin/install -C' |
| '--with-methods=opt dbg' |
| '--prefix=/Users/petejw/projects/libmesh_git/installed' |
| '--enable-perflog' |
| '--enable-tracefiles' |
| '--disable-blocked-storage' |
| '--enable-default-comm-world' |
| '--enable-tecio' |
| '--enable-unique-ptr' |
| '--enable-ifem' |
| 'PETSC_DIR=/opt/moose/petsc/mpich_petsc-3.6.1/clang-opt-superlu' |
| 'SLEPC_DIR=/opt/petejw/slepc/3.6.1' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
| '--disable-netcdf-4' |
| '--disable-testsets' |
| 'CXX=mpicxx' |
| 'CC=mpicc' |
| 'F77=mpif77' |
| 'FC=mpif90' |
| 'CPPFLAGS= ' |
| 'LIBS= ' |
-------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
| Matrix Assembly Performance: Alive time=0.125934, Active time=0.107223 |
------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|------------------------------------------------------------------------------------------------------------|
| |
| BCs 2931 0.0431 0.000015 0.0431 0.000015 40.18 40.18 |
| Fe 2931 0.0181 0.000006 0.0181 0.000006 16.88 16.88 |
| Ke 2931 0.0093 0.000003 0.0093 0.000003 8.69 8.69 |
| elem init 2931 0.0283 0.000010 0.0283 0.000010 26.44 26.44 |
| matrix insertion 2931 0.0084 0.000003 0.0084 0.000003 7.82 7.82 |
------------------------------------------------------------------------------------------------------------
| Totals: 14655 0.1072 100.00 |
------------------------------------------------------------------------------------------------------------
-----------------------------------------------------------------------------------------------------------------
| libMesh Performance: Alive time=0.35384, Active time=0.323716 |
-----------------------------------------------------------------------------------------------------------------
| Event nCalls Total Time Avg Time Total Time Avg Time % of Active Time |
| w/o Sub w/o Sub With Sub With Sub w/o S With S |
|-----------------------------------------------------------------------------------------------------------------|
| |
| |
| DofMap |
| add_neighbors_to_send_list() 1 0.0022 0.002166 0.0022 0.002166 0.67 0.67 |
| build_constraint_matrix() 2931 0.0069 0.000002 0.0069 0.000002 2.12 2.12 |
| build_sparsity() 1 0.0401 0.040105 0.0430 0.043017 12.39 13.29 |
| cnstrn_elem_mat_vec() 2931 0.0062 0.000002 0.0062 0.000002 1.91 1.91 |
| create_dof_constraints() 1 0.0088 0.008810 0.0130 0.013032 2.72 4.03 |
| distribute_dofs() 1 0.0016 0.001572 0.0085 0.008455 0.49 2.61 |
| dof_indices() 40989 0.0094 0.000000 0.0094 0.000000 2.90 2.90 |
| prepare_send_list() 2 0.0000 0.000000 0.0000 0.000000 0.00 0.00 |
| reinit() 1 0.0069 0.006883 0.0069 0.006883 2.13 2.13 |
| |
| EquationSystems |
| build_solution_vector() 2 0.0106 0.005282 0.0156 0.007814 3.26 4.83 |
| |
| ExodusII_IO |
| write_nodal_data() 1 0.0118 0.011776 0.0118 0.011776 3.64 3.64 |
| |
| FE |
| compute_shape_functions() 5649 0.0223 0.000004 0.0223 0.000004 6.90 6.90 |
| init_shape_functions() 2719 0.0004 0.000000 0.0004 0.000000 0.13 0.13 |
| inverse_map() 4068 0.0015 0.000000 0.0015 0.000000 0.46 0.46 |
| |
| FEMap |
| compute_affine_map() 5649 0.0088 0.000002 0.0088 0.000002 2.72 2.72 |
| compute_face_map() 2718 0.0023 0.000001 0.0023 0.000001 0.71 0.71 |
| init_face_shape_functions() 1 0.0000 0.000008 0.0000 0.000008 0.00 0.00 |
| init_reference_to_physical_map() 2719 0.0227 0.000008 0.0227 0.000008 7.01 7.01 |
| |
| GMVIO |
| write_nodal_data() 1 0.0398 0.039793 0.0398 0.039793 12.29 12.29 |
| |
| Mesh |
| find_neighbors() 2 0.0297 0.014873 0.0297 0.014873 9.19 9.19 |
| renumber_nodes_and_elem() 4 0.0007 0.000175 0.0007 0.000175 0.22 0.22 |
| |
| MeshOutput |
| write_equation_systems() 2 0.0000 0.000018 0.0672 0.033617 0.01 20.77 |
| |
| MeshRefinement |
| _refine_elements() 1 0.0125 0.012493 0.0269 0.026927 3.86 8.32 |
| add_node() 43136 0.0110 0.000000 0.0110 0.000000 3.41 3.41 |
| make_flags_parallel_consistent() 1 0.0002 0.000171 0.0002 0.000171 0.05 0.05 |
| make_refinement_compatible() 1 0.0001 0.000089 0.0001 0.000089 0.03 0.03 |
| |
| MeshTools::Generation |
| build_cube() 1 0.0014 0.001398 0.0014 0.001398 0.43 0.43 |
| |
| Parallel |
| allgather() 1 0.0000 0.000000 0.0000 0.000000 0.00 0.00 |
| |
| Partitioner |
| single_partition() 2 0.0005 0.000261 0.0005 0.000261 0.16 0.16 |
| |
| PetscLinearSolver |
| solve() 1 0.0123 0.012263 0.0123 0.012263 3.79 3.79 |
| |
| System |
| assemble() 1 0.0530 0.053024 0.1260 0.126005 16.38 38.92 |
| |
| TopologyMap |
| init() 1 0.0000 0.000046 0.0000 0.000046 0.01 0.01 |
-----------------------------------------------------------------------------------------------------------------
| Totals: 113539 0.3237 100.00 |
-----------------------------------------------------------------------------------------------------------------
***************************************************************
* Done Running Example subdomains_ex1:
* example-opt -d 3 -n 15
***************************************************************