ubique/lib/matarrs/getrow.js

A mathematical and quantitative library for Javascript and Node.js

/**
 * Indexing
 */
 module.exports = function($u) {
/**
 * @method getrow
 * @summary Get a row of matrix
 * @description  Get a row of a matrix
 * 
 * @param  {matrix} x matrix of elements
 * @param  {number} n row number (indexing from 0 to n - 1)
 * @return {array}   
 *
 * @example
 * ubique.getrow([[5,6,5],[7,8,-1]],0);
 * // [ 5, 6, 5 ]
 * 
 * ubique.getrow([[5,6,5],[7,8,-1]],1);
 * // [ 7, 8, -1 ]
 */
 $u.getrow = function(x,n) {
  if (arguments.length === 0) {
    throw new Error('not enough input arguments');
  }
  n = n == null ? 0 : n;
  if ($u.isarray(x)) {
   throw new Error('input must be a matrix');
  }
  if (!$u.isinteger(n) || n < 0 || n >= $u.nrows(x)) {
    throw new Error('row must be an integer between 0 and N - 1 rows');
  }
  return x[n];
 }

}