示例#1
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    def create_state_from_snapshot(self, snapshot):
        """Create the simulations state from a `Snapshot`.

        Args:
            snapshot (Snapshot or gsd.hoomd.Snapshot): Snapshot to initialize
                the state from. A `gsd.hoomd.Snapshot` will first be
                converted to a `hoomd.Snapshot`.


        When `timestep` is `None` before calling, `create_state_from_snapshot`
        sets `timestep` to 0.
        """
        if self.state is not None:
            raise RuntimeError("Cannot initialize more than once\n")

        if isinstance(snapshot, Snapshot):
            # snapshot is hoomd.Snapshot
            self._state = State(self, snapshot)
        elif _match_class_path(snapshot, 'gsd.hoomd.Snapshot'):
            # snapshot is gsd.hoomd.Snapshot
            snapshot = Snapshot.from_gsd_snapshot(snapshot,
                                                  self._device.communicator)
            self._state = State(self, snapshot)
        else:
            raise TypeError(
                "Snapshot must be a hoomd.Snapshot or gsd.hoomd.Snapshot.")

        step = 0
        if self.timestep is not None:
            step = self.timestep

        self._init_system(step)
示例#2
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    def create_state_from_snapshot(self,
                                   snapshot,
                                   domain_decomposition=(None, None, None)):
        """Create the simulation state from a `Snapshot`.

        Args:
            snapshot (Snapshot or gsd.hoomd.Snapshot): Snapshot to initialize
                the state from. A `gsd.hoomd.Snapshot` will first be
                converted to a `hoomd.Snapshot`.

            domain_decomposition (tuple): Choose how to distribute the state
                across MPI ranks with domain decomposition. Provide a tuple
                of 3 integers indicating the number of evenly spaced domains in
                the x, y, and z directions (e.g. ``(8,4,2)``). Provide a tuple
                of 3 lists of floats to set the fraction of the simulation box
                to include in each domain. The sum of each list of floats must
                be 1.0 (e.g. ``([0.25, 0.75], [0.2, 0.8], [1.0])``).

        When `timestep` is `None` before calling, `create_state_from_snapshot`
        sets `timestep` to 0.

        Note:
            Set any or all of the ``domain_decomposition`` tuple elements to
            `None` and `create_state_from_gsd` will select a value that
            minimizes the surface area between the domains (e.g.
            ``(2,None,None)``). The domains are spaced evenly along each
            automatically selected direction. The default value of ``(None,
            None, None)`` will automatically select the number of domains in all
            directions.

        See Also:
            `State.get_snapshot`

            `State.set_snapshot`
        """
        if self._state is not None:
            raise RuntimeError("Cannot initialize more than once\n")

        if isinstance(snapshot, Snapshot):
            # snapshot is hoomd.Snapshot
            self._state = State(self, snapshot, domain_decomposition)
        elif _match_class_path(snapshot, 'gsd.hoomd.Snapshot'):
            # snapshot is gsd.hoomd.Snapshot
            snapshot = Snapshot.from_gsd_snapshot(snapshot,
                                                  self._device.communicator)
            self._state = State(self, snapshot, domain_decomposition)
        else:
            raise TypeError(
                "Snapshot must be a hoomd.Snapshot or gsd.hoomd.Snapshot.")

        step = 0
        if self.timestep is not None:
            step = self.timestep

        self._init_system(step)
示例#3
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    def create_state_from_gsd(self, filename, frame=-1):
        """Create the simulation state from a GSD file.

        Args:
            filename (str): GSD file to read

            frame (int): Index of the frame to read from the file. Negative
                values index back from the last frame in the file.
        """
        if self.state is not None:
            raise RuntimeError("Cannot initialize more than once\n")
        filename = _hoomd.mpi_bcast_str(filename, self.device._cpp_exec_conf)
        # Grab snapshot and timestep
        reader = _hoomd.GSDReader(self.device._cpp_exec_conf, filename,
                                  abs(frame), frame < 0)
        snapshot = Snapshot._from_cpp_snapshot(reader.getSnapshot(),
                                               self.device.communicator)

        step = reader.getTimeStep() if self.timestep is None else self.timestep
        self._state = State(self, snapshot)

        reader.clearSnapshot()
        # Store System and Reader for Operations
        self._cpp_sys = _hoomd.System(self.state._cpp_sys_def, step)
        self._init_communicator()
        self.operations._store_reader(reader)
示例#4
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    def create_state_from_snapshot(self, snapshot):
        """Create the simulations state from a `Snapshot`.

        Args:
            snapshot (Snapshot): Snapshot to initialize the state from.

        When `timestep` is `None` before calling, `create_state_from_snapshot`
        sets `timestep` to 0.

        Warning:
            *snapshot* must be a `hoomd.Snapshot`. Use `create_state_from_gsd`
            to read GSD files. `create_state_from_snapshot` does not support
            ``gsd.hoomd.Snapshot`` objects from the ``gsd`` Python package.
        """
        if self.state is not None:
            raise RuntimeError("Cannot initialize more than once\n")

        self._state = State(self, snapshot)

        step = 0
        if self.timestep is not None:
            step = self.timestep

        # Store System and Reader for Operations
        self._cpp_sys = _hoomd.System(self.state._cpp_sys_def, step)
        self._init_communicator()
示例#5
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    def create_state_from_gsd(self,
                              filename,
                              frame=-1,
                              domain_decomposition=(None, None, None)):
        """Create the simulation state from a GSD file.

        Args:
            filename (str): GSD file to read

            frame (int): Index of the frame to read from the file. Negative
                values index back from the last frame in the file.

            domain_decomposition (tuple): Choose how to distribute the state
                across MPI ranks with domain decomposition. Provide a tuple
                of 3 integers indicating the number of evenly spaced domains in
                the x, y, and z directions (e.g. ``(8,4,2)``). Provide a tuple
                of 3 lists of floats to set the fraction of the simulation box
                to include in each domain. The sum of each list of floats must
                be 1.0 (e.g. ``([0.25, 0.75], [0.2, 0.8], [1.0])``).

        When `timestep` is `None` before calling, `create_state_from_gsd`
        sets `timestep` to the value in the selected GSD frame in the file.

        Note:
            Set any or all of the ``domain_decomposition`` tuple elements to
            `None` and `create_state_from_gsd` will select a value that
            minimizes the surface area between the domains (e.g.
            ``(2,None,None)``). The domains are spaced evenly along each
            automatically selected direction. The default value of ``(None,
            None, None)`` will automatically select the number of domains in all
            directions.
        """
        if self._state is not None:
            raise RuntimeError("Cannot initialize more than once\n")
        filename = _hoomd.mpi_bcast_str(filename, self.device._cpp_exec_conf)
        # Grab snapshot and timestep
        reader = _hoomd.GSDReader(self.device._cpp_exec_conf, filename,
                                  abs(frame), frame < 0)
        snapshot = Snapshot._from_cpp_snapshot(reader.getSnapshot(),
                                               self.device.communicator)

        step = reader.getTimeStep() if self.timestep is None else self.timestep
        self._state = State(self, snapshot, domain_decomposition)

        reader.clearSnapshot()

        self._init_system(step)