text: /* ----------------------------------------------------------------------
   * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
   *
   * $Date:        19. March 2015
   * $Revision:   V.1.4.5
   *
   * Project:         CMSIS DSP Library
   * Title:        arm_fir_sparse_init_q31.c
   *
   * Description:	Q31 sparse FIR filter initialization function.
   *
   * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *   - Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   *   - Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in
   *     the documentation and/or other materials provided with the
   *     distribution.
   *   - Neither the name of ARM LIMITED nor the names of its contributors
   *     may be used to endorse or promote products derived from this
   *     software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   * ---------------------------------------------------------------------------*/
  
  #include "arm_math.h"
  
  /**
   * @ingroup groupFilters
   */
  
  /**
   * @addtogroup FIR_Sparse
   * @{
   */
  
  /**
   * @brief  Initialization function for the Q31 sparse FIR filter.
   * @param[in,out] *S         points to an instance of the Q31 sparse FIR structure.
   * @param[in]     numTaps    number of nonzero coefficients in the filter.
   * @param[in]     *pCoeffs   points to the array of filter coefficients.
   * @param[in]     *pState    points to the state buffer.
   * @param[in]     *pTapDelay points to the array of offset times.
   * @param[in]     maxDelay   maximum offset time supported.
   * @param[in]     blockSize  number of samples that will be processed per block.
   * @return none
   *
   * <b>Description:</b>
   * \par
   * <code>pCoeffs</code> holds the filter coefficients and has length <code>numTaps</code>.
   * <code>pState</code> holds the filter's state variables and must be of length
   * <code>maxDelay + blockSize</code>, where <code>maxDelay</code>
   * is the maximum number of delay line values.
   * <code>blockSize</code> is the number of words processed by <code>arm_fir_sparse_q31()</code> function.
   */
  
  void arm_fir_sparse_init_q31(
    arm_fir_sparse_instance_q31 *S,
    uint16_t                     numTaps,
    q31_t *                      pCoeffs,
    q31_t *                      pState,
    int32_t *                    pTapDelay,
    uint16_t                     maxDelay,
    uint32_t                     blockSize)
  {
      /* Assign filter taps */
      S->numTaps = numTaps;
  
      /* Assign coefficient pointer */
      S->pCoeffs = pCoeffs;
  
      /* Assign TapDelay pointer */
      S->pTapDelay = pTapDelay;
  
      /* Assign MaxDelay */
      S->maxDelay = maxDelay;
  
      /* reset the stateIndex to 0 */
      S->stateIndex = 0u;
  
      /* Clear state buffer and size is always maxDelay + blockSize */
      memset(pState, 0, (maxDelay + blockSize) * sizeof(q31_t));
  
      /* Assign state pointer */
      S->pState = pState;
  }
  
  /**
   * @} end of FIR_Sparse group
   */
  