.. index:: pair: struct; CPMDCStressTensor
.. _doxid-struct_c_p_m_d_c_stress_tensor:

struct CPMDCStressTensor
========================

.. toctree::
	:hidden:

Overview
~~~~~~~~

Cartesian stress tensor after a successful PEF evaluation. :ref:`More...<details-struct_c_p_m_d_c_stress_tensor>`


.. ref-code-block:: cpp
	:class: doxyrest-overview-code-block

	#include <cpmdc.h>
	
	struct CPMDCStressTensor {
		// fields
	
		int :ref:`valid<doxid-struct_c_p_m_d_c_stress_tensor_1a040d79094dfec598b51035b87f1ceb1d>`;
		double :ref:`values<doxid-struct_c_p_m_d_c_stress_tensor_1a7061f78949c193ef5285436a368780b3>`[9];
	};
.. _details-struct_c_p_m_d_c_stress_tensor:

Detailed Documentation
~~~~~~~~~~~~~~~~~~~~~~

Cartesian stress tensor after a successful PEF evaluation.

Layout is row-major [xx, xy, xz, yx, yy, yz, zx, zy, zz] in Hartree/Bohr^3 (OpenCPMD ``paiu/omega`` after ``totstr`` when ``cntltpres``). ``valid`` is set only when that tensor was computed for a periodic cell. A positive cell volume is not enough: an isolated (cluster/Hockney) box leaves ``valid`` unset. Returns 0 when ``out->valid`` is set; -1 when stress was not computed.

Fields
------

.. index:: pair: variable; valid
.. _doxid-struct_c_p_m_d_c_stress_tensor_1a040d79094dfec598b51035b87f1ceb1d:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	int valid

Non-zero only when stress was computed for a periodic cell.

.. index:: pair: variable; values
.. _doxid-struct_c_p_m_d_c_stress_tensor_1a7061f78949c193ef5285436a368780b3:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	double values[9]

Row-major ``[xx, xy, xz, yx, yy, yz, zx, zy, zz]``, Hartree/Bohr^3.