Source code for deltasigma._padb

# -*- coding: utf-8 -*-
# _padb.py
# This module provides the padb function.
# Copyright 2013 Giuseppe Venturini
# This file is part of python-deltasigma.
#
# python-deltasigma is a 1:1 Python replacement of Richard Schreier's
# MATLAB delta sigma toolbox (aka "delsigma"), upon which it is heavily based.
# The delta sigma toolbox is (c) 2009, Richard Schreier.
#
# python-deltasigma is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# LICENSE file for the licensing terms.

"""This module provides the padb() function, which pads a matrix on the 
bottom.
"""

import numpy as np


[docs]def padb(x, n, val=0.): """Pad a matrix ``x`` on the bottom to length ``n`` with value ``val``. **Parameters:** x : ndarray The matrix to be padded. n : int The number of rows of the matrix after padding. val : scalar, optional The value to be used used for padding. .. note:: A 1-d array, for example ``a.shape == (N,)`` is reshaped to be a 1 column array: ``a.reshape((N, 1))`` The empty matrix is assumed to be have 1 empty column. **Returns:** xp : 2-d ndarray The padded matrix. """ if len(x.shape) == 1: xp = x.reshape((x.shape[0], 1)) else: xp = x y = np.concatenate((xp, val*np.ones((n - xp.shape[0], xp.shape[1])) ), axis=0) return y