python: doc and example updates
This commit is contained in:
committed by
Richard Berger
parent
e45ef5adc0
commit
754aa1c73f
@ -104,6 +104,5 @@ Tutorials howto
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Howto_lammps_gui
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Howto_moltemplate
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Howto_pylammps
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Howto_python
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Howto_wsl
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@ -3,4 +3,4 @@ PyLammps Tutorial
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The PyLammps interface is deprecated and will be removed in a future release of
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LAMMPS. As such, the PyLammps version of this tutorial has been removed and is
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replaced by the :doc:`Howto_python`.
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replaced by the :doc:`Python_head`.
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@ -26,14 +26,30 @@ against invalid accesses.
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lmp = lammps()
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lmp.file("in.sysinit")
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# Read/Write access via ctypes
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nlocal = lmp.extract_global("nlocal")
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x = lmp.extract_atom("x")
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for i in range(nlocal):
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print("(x,y,z) = (", x[i][0], x[i][1], x[i][2], ")")
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# Read/Write access via NumPy arrays
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atom_id = L.numpy.extract_atom("id")
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atom_type = L.numpy.extract_atom("type")
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x = L.numpy.extract_atom("x")
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v = L.numpy.extract_atom("v")
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f = L.numpy.extract_atom("f")
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# set position in 2D simulation
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x[0] = (1.0, 0.0)
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# set position in 3D simulation
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x[0] = (1.0, 0.0, 1.)
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lmp.close()
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**Methods**:
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* :py:meth:`extract_atom() <lammps.lammps.extract_atom()>`: extract a per-atom quantity
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@ -6,11 +6,10 @@ Creating or deleting a LAMMPS object
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====================================
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With the Python interface the creation of a :cpp:class:`LAMMPS
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<LAMMPS_NS::LAMMPS>` instance is included in the constructors for the
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:py:class:`lammps <lammps.lammps>`, :py:class:`PyLammps <lammps.PyLammps>`,
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and :py:class:`IPyLammps <lammps.IPyLammps>` classes.
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Internally it will call either :cpp:func:`lammps_open` or :cpp:func:`lammps_open_no_mpi` from the C
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library API to create the class instance.
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<LAMMPS_NS::LAMMPS>` instance is included in the constructor for the
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:py:class:`lammps <lammps.lammps>` class. Internally it will call either
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:cpp:func:`lammps_open` or :cpp:func:`lammps_open_no_mpi` from the C library
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API to create the class instance.
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All arguments are optional. The *name* argument allows loading a
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LAMMPS shared library that is named ``liblammps_machine.so`` instead of
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@ -26,7 +26,7 @@ demonstrates the use of :py:func:`lammps.file()`, :py:func:`lammps.command()`,
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lmp.command('variable zpos index 1.0')
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# create 10 groups with 10 atoms each
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cmds = ["group g{} id {}:{}".format(i,10*i+1,10*(i+1)) for i in range(10)]
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cmds = [f"group g{i} id {10*i+1}:{10*(i+1)}" for i in range(10)]
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lmp.commands_list(cmds)
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# run commands from a multi-line string
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@ -38,10 +38,9 @@ demonstrates the use of :py:func:`lammps.file()`, :py:func:`lammps.command()`,
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"""
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lmp.commands_string(block)
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Unlike the lammps API, the PyLammps/IPyLammps APIs allow running LAMMPS
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commands by calling equivalent member functions of :py:class:`PyLammps <lammps.PyLammps>`
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and :py:class:`IPyLammps <lammps.IPyLammps>` instances.
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For convenience, the :py:class:`lammps <lammps.lammps>` class also provides a
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command wrapper ``cmd`` that turns any LAMMPS command into a regular function
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call.
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For instance, the following LAMMPS command
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@ -49,8 +48,7 @@ For instance, the following LAMMPS command
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region box block 0 10 0 5 -0.5 0.5
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can be executed using with the lammps API with the following Python code if ``lmp`` is an
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instance of :py:class:`lammps <lammps.lammps>`:
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would normally be executed with the following Python code:
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.. code-block:: python
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@ -59,7 +57,7 @@ instance of :py:class:`lammps <lammps.lammps>`:
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lmp = lammps()
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lmp.command("region box block 0 10 0 5 -0.5 0.5")
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With the PyLammps interface, any LAMMPS command can be split up into arbitrary parts.
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With the ``cmd`` wrapper, any LAMMPS command can be split up into arbitrary parts.
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These parts are then passed to a member function with the name of the :doc:`command <Commands_all>`.
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For the :doc:`region <region>` command that means the :code:`region()` method can be called.
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The arguments of the command can be passed as one string, or
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@ -82,25 +80,31 @@ member function takes the entire parameter list and transparently merges it to a
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string.
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The benefit of this approach is avoiding redundant command calls and easier
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parameterization. In the lammps API parameterization needed to be done
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manually by creating formatted command strings.
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parameterization. With `command`, `commands_list`, and `commands_string` the
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parameterization needed to be done manually by creating formatted command
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strings.
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.. code-block:: python
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lmp.command("region box block %f %f %f %f %f %f" % (xlo, xhi, ylo, yhi, zlo, zhi))
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In contrast, methods of PyLammps accept parameters directly and will convert
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In contrast, methods of the `cmd` wrapper accept parameters directly and will convert
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them automatically to a final command string.
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.. code-block:: python
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L.cmd.region("box block", xlo, xhi, ylo, yhi, zlo, zhi)
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.. note::
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When running in IPython you can use Tab-completion after ``L.cmd.`` to see
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all available LAMMPS commands.
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Using these facilities, the previous example shown above can be rewritten as follows:
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.. code-block:: python
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from lammps import PyLammps
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from lammps import lammps
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L = lammps()
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# read commands from file 'in.melt'
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@ -15,6 +15,7 @@ together.
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Python_call
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Python_formats
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Python_examples
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Python_jupyter
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Python_error
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Python_trouble
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48
doc/src/Python_jupyter.rst
Normal file
48
doc/src/Python_jupyter.rst
Normal file
@ -0,0 +1,48 @@
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Using LAMMPS in IPython notebooks and Jupyter
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=============================================
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If the LAMMPS Python package is installed for the same Python interpreter as
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`IPython <ipython>`_, you can use LAMMPS directly inside of an IPython notebook inside of
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Jupyter. `Jupyter <juypter>`_ is a powerful integrated development environment (IDE) for
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many dynamic languages like Python, Julia and others, which operates inside of
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any web browser. Besides auto-completion and syntax highlighting it allows you
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to create formatted documents using Markup, mathematical formulas, graphics and
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animations intermixed with executable Python code. It is a great format for
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tutorials and showcasing your latest research.
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The easiest way to install it is via ``pip``:
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.. code-block:: bash
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pip install jupyter
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To launch an instance of Jupyter simply run the following command inside your
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Python environment:
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.. code-block:: bash
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jupyter notebook
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.. _ipython: https://ipython.org/
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.. _jupyter: https://jupyter.org/
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Interactive Python Examples
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---------------------------
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Examples of IPython notebooks can be found in the ``python/examples/ipython``
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subdirectory. They require LAMMPS to be compiled as shared library with PYTHON,
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PNG, JPEG and FFMPEG support.
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To open these notebooks launch ``jupyter notebook index.ipynb`` inside this
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directory. The opened file provides an overview of the available examples.
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- Example 1: Using LAMMPS with Python (``simple.ipynb``)
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- Example 2: Analyzing LAMMPS thermodynamic data (``thermo.ipynb``)
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- Example 3: Working with Per-Atom Data (``atoms.ipynb``)
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- Example 4: Working with LAMMPS variables (``variables.ipynb``)
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- Example 5: Validating a dihedral potential (``dihedrals/dihedral.ipynb``)
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- Example 6: Running a Monte Carlo relaxation (``montecarlo/mc.ipynb``)
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.. note::
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Typically clicking a link in Jupyter will open a new tab, which might be blocked by your pop-up blocker.
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@ -14,9 +14,7 @@ session with the ``import`` command.
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Alternative interfaces such as :py:class:`PyLammps <lammps.PyLammps>` and
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:py:class:`IPyLammps <lammps.IPyLammps>` classes have been deprecated and
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will be removed in a future version of LAMMPS. The :doc:`Howto_pylammps` has
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also been replaced by a reworked :doc:`Howto_python` that showcases how to
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use the modern Python API facilities instead.
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will be removed in a future version of LAMMPS.
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.. _mpi4py_url: https://mpi4py.readthedocs.io
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@ -4,95 +4,52 @@ Compute, fixes, variables
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This section documents accessing or modifying data from objects like
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computes, fixes, or variables in LAMMPS using the :py:mod:`lammps` module.
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.. tabs::
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For :py:meth:`lammps.extract_compute() <lammps.lammps.extract_compute()>` and
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:py:meth:`lammps.extract_fix() <lammps.lammps.extract_fix()>`, the global, per-atom,
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or local data calculated by the compute or fix can be accessed. What is returned
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depends on whether the compute or fix calculates a scalar or vector or array.
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For a scalar, a single double value is returned. If the compute or fix calculates
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a vector or array, a pointer to the internal LAMMPS data is returned, which you can
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use via normal Python subscripting.
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.. tab:: lammps API
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The one exception is that for a fix that calculates a
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global vector or array, a single double value from the vector or array
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is returned, indexed by I (vector) or I and J (array). I,J are
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zero-based indices.
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See the :doc:`Howto output <Howto_output>` page for a discussion of
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global, per-atom, and local data, and of scalar, vector, and array
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data types. See the doc pages for individual :doc:`computes <compute>`
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and :doc:`fixes <fix>` for a description of what they calculate and
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store.
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For :py:meth:`lammps.extract_compute() <lammps.lammps.extract_compute()>` and
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:py:meth:`lammps.extract_fix() <lammps.lammps.extract_fix()>`, the global, per-atom,
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or local data calculated by the compute or fix can be accessed. What is returned
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depends on whether the compute or fix calculates a scalar or vector or array.
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For a scalar, a single double value is returned. If the compute or fix calculates
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a vector or array, a pointer to the internal LAMMPS data is returned, which you can
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use via normal Python subscripting.
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For :py:meth:`lammps.extract_variable() <lammps.lammps.extract_variable()>`,
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an :doc:`equal-style or atom-style variable <variable>` is evaluated and
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its result returned.
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The one exception is that for a fix that calculates a
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global vector or array, a single double value from the vector or array
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is returned, indexed by I (vector) or I and J (array). I,J are
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zero-based indices.
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See the :doc:`Howto output <Howto_output>` page for a discussion of
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global, per-atom, and local data, and of scalar, vector, and array
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data types. See the doc pages for individual :doc:`computes <compute>`
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and :doc:`fixes <fix>` for a description of what they calculate and
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store.
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For equal-style variables a single ``c_double`` value is returned and the
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group argument is ignored. For atom-style variables, a vector of
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``c_double`` is returned, one value per atom, which you can use via normal
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Python subscripting. The values will be zero for atoms not in the
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specified group.
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For :py:meth:`lammps.extract_variable() <lammps.lammps.extract_variable()>`,
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an :doc:`equal-style or atom-style variable <variable>` is evaluated and
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its result returned.
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:py:meth:`lammps.numpy.extract_compute() <lammps.numpy_wrapper.numpy_wrapper.extract_compute()>`,
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:py:meth:`lammps.numpy.extract_fix() <lammps.numpy_wrapper.numpy_wrapper.extract_fix()>`, and
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:py:meth:`lammps.numpy.extract_variable() <lammps.numpy_wrapper.numpy_wrapper.extract_variable()>` are
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equivalent NumPy implementations that return NumPy arrays instead of ``ctypes`` pointers.
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For equal-style variables a single ``c_double`` value is returned and the
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group argument is ignored. For atom-style variables, a vector of
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``c_double`` is returned, one value per atom, which you can use via normal
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Python subscripting. The values will be zero for atoms not in the
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specified group.
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The :py:meth:`lammps.set_variable() <lammps.lammps.set_variable()>` method sets an
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existing string-style variable to a new string value, so that subsequent LAMMPS
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commands can access the variable.
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:py:meth:`lammps.numpy.extract_compute() <lammps.numpy_wrapper.numpy_wrapper.extract_compute()>`,
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:py:meth:`lammps.numpy.extract_fix() <lammps.numpy_wrapper.numpy_wrapper.extract_fix()>`, and
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:py:meth:`lammps.numpy.extract_variable() <lammps.numpy_wrapper.numpy_wrapper.extract_variable()>` are
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equivalent NumPy implementations that return NumPy arrays instead of ``ctypes`` pointers.
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**Methods**:
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The :py:meth:`lammps.set_variable() <lammps.lammps.set_variable()>` method sets an
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existing string-style variable to a new string value, so that subsequent LAMMPS
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commands can access the variable.
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* :py:meth:`lammps.extract_compute() <lammps.lammps.extract_compute()>`: extract value(s) from a compute
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* :py:meth:`lammps.extract_fix() <lammps.lammps.extract_fix()>`: extract value(s) from a fix
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* :py:meth:`lammps.extract_variable() <lammps.lammps.extract_variable()>`: extract value(s) from a variable
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* :py:meth:`lammps.set_variable() <lammps.lammps.set_variable()>`: set existing named string-style variable to value
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**Methods**:
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**NumPy Methods**:
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* :py:meth:`lammps.extract_compute() <lammps.lammps.extract_compute()>`: extract value(s) from a compute
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* :py:meth:`lammps.extract_fix() <lammps.lammps.extract_fix()>`: extract value(s) from a fix
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* :py:meth:`lammps.extract_variable() <lammps.lammps.extract_variable()>`: extract value(s) from a variable
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* :py:meth:`lammps.set_variable() <lammps.lammps.set_variable()>`: set existing named string-style variable to value
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**NumPy Methods**:
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* :py:meth:`lammps.numpy.extract_compute() <lammps.numpy_wrapper.numpy_wrapper.extract_compute()>`: extract value(s) from a compute, return arrays as numpy arrays
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* :py:meth:`lammps.numpy.extract_fix() <lammps.numpy_wrapper.numpy_wrapper.extract_fix()>`: extract value(s) from a fix, return arrays as numpy arrays
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* :py:meth:`lammps.numpy.extract_variable() <lammps.numpy_wrapper.numpy_wrapper.extract_variable()>`: extract value(s) from a variable, return arrays as numpy arrays
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.. tab:: PyLammps/IPyLammps API
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PyLammps and IPyLammps classes currently do not add any additional ways of
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retrieving information out of computes and fixes. This information can still be accessed by using the lammps API:
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.. code-block:: python
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L.lmp.extract_compute(...)
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L.lmp.extract_fix(...)
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# OR
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L.lmp.numpy.extract_compute(...)
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L.lmp.numpy.extract_fix(...)
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LAMMPS variables can be both defined and accessed via the :py:class:`PyLammps <lammps.PyLammps>` interface.
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To define a variable you can use the :doc:`variable <variable>` command:
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.. code-block:: python
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L.variable("a index 2")
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A dictionary of all variables is returned by the :py:attr:`PyLammps.variables <lammps.PyLammps.variables>` property:
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you can access an individual variable by retrieving a variable object from the
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``L.variables`` dictionary by name
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.. code-block:: python
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a = L.variables['a']
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The variable value can then be easily read and written by accessing the value
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property of this object.
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.. code-block:: python
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print(a.value)
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a.value = 4
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* :py:meth:`lammps.numpy.extract_compute() <lammps.numpy_wrapper.numpy_wrapper.extract_compute()>`: extract value(s) from a compute, return arrays as numpy arrays
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* :py:meth:`lammps.numpy.extract_fix() <lammps.numpy_wrapper.numpy_wrapper.extract_fix()>`: extract value(s) from a fix, return arrays as numpy arrays
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* :py:meth:`lammps.numpy.extract_variable() <lammps.numpy_wrapper.numpy_wrapper.extract_variable()>`: extract value(s) from a variable, return arrays as numpy arrays
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@ -2,14 +2,8 @@ System properties
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=================
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Similar to what is described in :doc:`Library_properties`, the instances of
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:py:class:`lammps <lammps.lammps>`, :py:class:`PyLammps <lammps.PyLammps>`, or
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:py:class:`IPyLammps <lammps.IPyLammps>` can be used to extract different kinds
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of information about the active LAMMPS instance and also to modify some of it. The
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main difference between the interfaces is how the information is exposed.
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While the :py:class:`lammps <lammps.lammps>` is just a thin layer that wraps C API calls,
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:py:class:`PyLammps <lammps.PyLammps>` and :py:class:`IPyLammps <lammps.IPyLammps>` expose
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information as objects and properties.
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:py:class:`lammps <lammps.lammps>` can be used to extract different kinds
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of information about the active LAMMPS instance and also to modify some of it.
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In some cases the data returned is a direct reference to the original data
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inside LAMMPS cast to ``ctypes`` pointers. Where possible, the wrappers will
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@ -25,113 +19,38 @@ against invalid accesses.
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accordingly. These arrays can change sizes and order at every neighbor list
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rebuild and atom sort event as atoms are migrating between subdomains.
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.. tabs::
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.. code-block:: python
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.. tab:: lammps API
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from lammps import lammps
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.. code-block:: python
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lmp = lammps()
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lmp.file("in.sysinit")
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from lammps import lammps
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natoms = lmp.get_natoms()
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print(f"running simulation with {natoms} atoms")
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lmp = lammps()
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lmp.file("in.sysinit")
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lmp.command("run 1000 post no");
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natoms = lmp.get_natoms()
|
||||
print(f"running simulation with {natoms} atoms")
|
||||
for i in range(10):
|
||||
lmp.command("run 100 pre no post no")
|
||||
pe = lmp.get_thermo("pe")
|
||||
ke = lmp.get_thermo("ke")
|
||||
print(f"PE = {pe}\nKE = {ke}")
|
||||
|
||||
lmp.command("run 1000 post no");
|
||||
lmp.close()
|
||||
|
||||
for i in range(10):
|
||||
lmp.command("run 100 pre no post no")
|
||||
pe = lmp.get_thermo("pe")
|
||||
ke = lmp.get_thermo("ke")
|
||||
print(f"PE = {pe}\nKE = {ke}")
|
||||
**Methods**:
|
||||
|
||||
lmp.close()
|
||||
* :py:meth:`version() <lammps.lammps.version()>`: return the numerical version id, e.g. LAMMPS 2 Sep 2015 -> 20150902
|
||||
* :py:meth:`get_thermo() <lammps.lammps.get_thermo()>`: return current value of a thermo keyword
|
||||
* :py:meth:`last_thermo() <lammps.lammps.last_thermo()>`: return a dictionary of the last thermodynamic output
|
||||
* :py:meth:`get_natoms() <lammps.lammps.get_natoms()>`: total # of atoms as int
|
||||
* :py:meth:`reset_box() <lammps.lammps.reset_box()>`: reset the simulation box size
|
||||
* :py:meth:`extract_setting() <lammps.lammps.extract_setting()>`: return a global setting
|
||||
* :py:meth:`extract_global() <lammps.lammps.extract_global()>`: extract a global quantity
|
||||
* :py:meth:`extract_box() <lammps.lammps.extract_box()>`: extract box info
|
||||
* :py:meth:`create_atoms() <lammps.lammps.create_atoms()>`: create N atoms with IDs, types, x, v, and image flags
|
||||
|
||||
**Methods**:
|
||||
**Properties**:
|
||||
|
||||
* :py:meth:`version() <lammps.lammps.version()>`: return the numerical version id, e.g. LAMMPS 2 Sep 2015 -> 20150902
|
||||
* :py:meth:`get_thermo() <lammps.lammps.get_thermo()>`: return current value of a thermo keyword
|
||||
* :py:meth:`last_thermo() <lammps.lammps.last_thermo()>`: return a dictionary of the last thermodynamic output
|
||||
* :py:meth:`get_natoms() <lammps.lammps.get_natoms()>`: total # of atoms as int
|
||||
* :py:meth:`reset_box() <lammps.lammps.reset_box()>`: reset the simulation box size
|
||||
* :py:meth:`extract_setting() <lammps.lammps.extract_setting()>`: return a global setting
|
||||
* :py:meth:`extract_global() <lammps.lammps.extract_global()>`: extract a global quantity
|
||||
* :py:meth:`extract_box() <lammps.lammps.extract_box()>`: extract box info
|
||||
* :py:meth:`create_atoms() <lammps.lammps.create_atoms()>`: create N atoms with IDs, types, x, v, and image flags
|
||||
|
||||
**Properties**:
|
||||
|
||||
* :py:attr:`last_thermo_step <lammps.lammps.last_thermo_step>`: the last timestep thermodynamic output was computed
|
||||
|
||||
.. tab:: PyLammps/IPyLammps API
|
||||
|
||||
In addition to the functions provided by :py:class:`lammps <lammps.lammps>`, :py:class:`PyLammps <lammps.PyLammps>` objects
|
||||
have several properties which allow you to query the system state:
|
||||
|
||||
L.system
|
||||
Is a dictionary describing the system such as the bounding box or number of atoms
|
||||
|
||||
L.system.xlo, L.system.xhi
|
||||
bounding box limits along x-axis
|
||||
|
||||
L.system.ylo, L.system.yhi
|
||||
bounding box limits along y-axis
|
||||
|
||||
L.system.zlo, L.system.zhi
|
||||
bounding box limits along z-axis
|
||||
|
||||
L.communication
|
||||
configuration of communication subsystem, such as the number of threads or processors
|
||||
|
||||
L.communication.nthreads
|
||||
number of threads used by each LAMMPS process
|
||||
|
||||
L.communication.nprocs
|
||||
number of MPI processes used by LAMMPS
|
||||
|
||||
L.fixes
|
||||
List of fixes in the current system
|
||||
|
||||
L.computes
|
||||
List of active computes in the current system
|
||||
|
||||
L.dump
|
||||
List of active dumps in the current system
|
||||
|
||||
L.groups
|
||||
List of groups present in the current system
|
||||
|
||||
**Retrieving the value of an arbitrary LAMMPS expressions**
|
||||
|
||||
LAMMPS expressions can be immediately evaluated by using the ``eval`` method. The
|
||||
passed string parameter can be any expression containing global :doc:`thermo` values,
|
||||
variables, compute or fix data (see :doc:`Howto_output`):
|
||||
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
result = L.eval("ke") # kinetic energy
|
||||
result = L.eval("pe") # potential energy
|
||||
|
||||
result = L.eval("v_t/2.0")
|
||||
|
||||
**Example**
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
from lammps import PyLammps
|
||||
|
||||
L = PyLammps()
|
||||
L.file("in.sysinit")
|
||||
|
||||
print(f"running simulation with {L.system.natoms} atoms")
|
||||
|
||||
L.run(1000, "post no");
|
||||
|
||||
for i in range(10):
|
||||
L.run(100, "pre no post no")
|
||||
pe = L.eval("pe")
|
||||
ke = L.eval("ke")
|
||||
print(f"PE = {pe}\nKE = {ke}")
|
||||
* :py:attr:`last_thermo_step <lammps.lammps.last_thermo_step>`: the last timestep thermodynamic output was computed
|
||||
|
||||
@ -4,7 +4,14 @@
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Example 3: Example 3: Using Atom Data"
|
||||
"<div style=\"text-align: center\"><a href=\"index.ipynb\">LAMMPS Python Tutorials</a></div>"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Example 3: Working with Per-Atom Data"
|
||||
]
|
||||
},
|
||||
{
|
||||
@ -133,248 +140,6 @@
|
||||
"L.ipython.image(zoom=1.8)"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"## Queries about LAMMPS simulation"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.system"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.system.natoms"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.system.nbonds"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.system.nbondtypes"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.communication"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.fixes"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.computes"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.dumps"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.groups"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"## Working with LAMMPS Variables"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variable(\"a index 2\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variable(\"t equal temp\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"import sys\n",
|
||||
"\n",
|
||||
"if sys.version_info < (3, 0):\n",
|
||||
" # In Python 2 'print' is a restricted keyword, which is why you have to use the lmp_print function instead.\n",
|
||||
" x = float(L.lmp_print('\"${a}\"'))\n",
|
||||
"else:\n",
|
||||
" # In Python 3 the print function can be redefined.\n",
|
||||
" # x = float(L.print('\"${a}\"')\")\n",
|
||||
" \n",
|
||||
" # To avoid a syntax error in Python 2 executions of this notebook, this line is packed into an eval statement\n",
|
||||
" x = float(eval(\"L.print('\\\"${a}\\\"')\"))\n",
|
||||
"x"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables['t'].value"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.eval(\"v_t/2.0\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variable(\"b index a b c\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables['b'].value"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.eval(\"v_b\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables['b'].definition"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variable(\"i loop 10\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.variables['i'].value"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.next(\"i\")\n",
|
||||
"L.variables['i'].value"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"L.expand(\"ke\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
@ -451,7 +216,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
@ -4,7 +4,14 @@
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Validating a dihedral potential"
|
||||
"<div style=\"text-align: center\"><a href=\"../index.ipynb\">LAMMPS Python Tutorials</a></div>"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Example 4: Validating a dihedral potential"
|
||||
]
|
||||
},
|
||||
{
|
||||
@ -232,7 +239,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
@ -5,7 +5,7 @@
|
||||
"id": "666d3036-47d5-44d2-bc1a-ca4b00a9e9b8",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# LAMMPS IPython Tutorial"
|
||||
"# LAMMPS Python Tutorials"
|
||||
]
|
||||
},
|
||||
{
|
||||
@ -25,7 +25,9 @@
|
||||
"\n",
|
||||
"- [Example 1: Using LAMMPS with Python](simple.ipynb)\n",
|
||||
"- [Example 2: Analyzing LAMMPS thermodynamic data](thermo.ipynb)\n",
|
||||
"- [Example 3: Using Atom Data](atom.ipynb)"
|
||||
"- [Example 3: Using Atom Data](atoms.ipynb)\n",
|
||||
"- [Example 4: Validating a dihedral potential](dihedrals/dihedral.ipynb)\n",
|
||||
"- [Example 5: Running a Monte Carlo relaxation](montecarlo/mc.ipynb)"
|
||||
]
|
||||
},
|
||||
{
|
||||
@ -53,7 +55,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
@ -4,7 +4,14 @@
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Monte Carlo Relaxation"
|
||||
"<div style=\"text-align: center\"><a href=\"../index.ipynb\">LAMMPS Python Tutorials</a></div>"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Example 5: Monte Carlo Relaxation"
|
||||
]
|
||||
},
|
||||
{
|
||||
@ -343,7 +350,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
@ -298,7 +298,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
@ -279,6 +279,24 @@
|
||||
"source": [
|
||||
"current_run.plot(x='Step', y='TotEng')"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Conclusion\n",
|
||||
"\n",
|
||||
"The Python interface gives you a powerful way of invoking and extracting simulation data while the simulation is running. Next we'll look at how to extract information about the atoms in your system.\n",
|
||||
"\n",
|
||||
"<div style=\"text-align:right\"><a href=\"atoms.ipynb\">Next</a>"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": []
|
||||
}
|
||||
],
|
||||
"metadata": {
|
||||
@ -297,7 +315,7 @@
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.6"
|
||||
"version": "3.12.7"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
|
||||
Reference in New Issue
Block a user