:py:mod:`bempp.api.grid.io`
===========================

.. py:module:: bempp.api.grid.io

.. autoapi-nested-parse::

   Routines for import and export.



Module Contents
---------------


Functions
~~~~~~~~~

.. autoapisummary::

   bempp.api.grid.io.import_grid
   bempp.api.grid.io.export
   bempp.api.grid.io._transform_array



.. py:function:: import_grid(filename)

   Import a grid.

   This routine uses the meshio library to export grids.
   A number of types are supported, including vtk, vtu,
   gmsh, dolphin xml. For a full list see

   https://github.com/nschloe/meshio



.. py:function:: export(filename, grid=None, grid_function=None, data_type=None, transformation=None, write_binary=True)

   Export grids and grid functions.

   This method internally uses the meshio library. For a full
   list of supported data types see

   https://github.com/nschloe/meshio

   Note that export of domain indices is only possible for Gmsh (.msh)
   format files.

   Parameters
   ----------
   filename : string
       The name of the file to write out. The data type is
       chosen based on the file ending.
   grid : Grid object
       A grid object to export.
   grid_function : GridFunction object
       Grid function to export
   data_type : string
       Either 'node' for vertex data or 'element' for data
       at element centers.
   transformation : string or callable
       One of 'real', 'imag', 'abs', 'log_abs',
       None or a callable object. Transforms the
       data on input. A callable must return numpy
       arrays with the same number of dimensions as
       the input. If transformation is None the data
       is not modified.
   write_binary : Boolean
       Use binary format (write_binary=True) for the
       data if supported by the file format.


.. py:function:: _transform_array(a, mode=None)

   Transform a data array.

   Parameters
   ----------
   a : np.ndarray
       Either a scalar array or a two dimensional data array.
   mode : string, callable or None
       One of 'real', 'imag', 'abs', 'log_abs', 'abs_squared',
       a transformation callable or None. The callable needs to take
       an input array of dimension 2 and return an array of
       dimension 2. If mode is None the input array is not modified.