<?php

namespace Arma\Internal;

/**
 * Interface for matrix-only operations.
 *
 * @package Arma\Internal
 */
interface MatBase
{
    /**
     * Set the elements of an object to zero, optionally first changing the size to specified dimensions.
     *
     * @param $n_rows[optional]
     * @param $n_cols[optional]
     * @return void
     */
    function zeros($n_rows, $n_cols);

    /**
     * Set all the elements of an object to one, optionally first changing the size to specified dimensions.
     *
     * @param $n_rows[optional]
     * @param $n_cols[optional]
     * @return void
     */
    function ones($n_rows, $n_cols);

    /**
     * Set the elements along the main diagonal to one and off-diagonal elements to zero, optionally
     * first changing the size to specified dimensions.
     *
     * @param $n_rows[optional]
     * @param $n_cols[optional]
     * @return void
     */
    function eye($n_rows, $n_cols);

    /**
     * Recreate the object according to given size specifications, with the elements taken from the
     * previous version of the object in a column-wise manner.
     *
     * The elements in the generated object are placed column-wise.
     *
     * @param $n_rows[optional]
     * @param $n_cols[optional]
     * @return void
     */
    function reshape($n_rows, $n_cols);

    /**
     * Recreate the object according to given size specifications, while preserving the elements
     * as well as the layout of the elements.
     *
     * @param $n_rows[optional]
     * @param $n_cols[optional]
     * @return void
     */
    function resize($n_rows, $n_cols);

    /**
     * Read/write access to a diagonal in a matrix.
     *
     * For k=0 the main diagonal is accessed. For k > 0, the k-th super-diagonal is accessed (top-right corner).
     * For k < 0, the k-th sub-diagonal is accessed (bottom-left corner).
     *
     * @param int $k
     * @return \Arma\Colvec
     */
    function diag($k = 0);

    /**
     * Check whether the matrix has exactly one column or one row.
     *
     * @return bool
     */
    function isVec();

    /**
     * Check whether the matrix has exactly one column.
     *
     * @return bool
     */
    function isColvec();

    /**
     * Check whether the matrix has exactly one row.
     *
     * @return bool
     */
    function isRowvec();

    /**
     * Check whether the matrix is square.
     *
     * @return bool
     */
    function isSquare();

    /**
     * Check whether the matrix is symmetric.
     *
     * @return bool
     */
    function isSymmetric();

    /**
     * Check whether the matrix is hermitian.
     *
     * @return bool
     */
    function isHermitian();
}