arm_min_q15.c

00001 /* ----------------------------------------------------------------------  
00002 * Copyright (C) 2010 ARM Limited. All rights reserved.  
00003 *  
00004 * $Date:        29. November 2010  
00005 * $Revision:    V1.0.3  
00006 *  
00007 * Project:      CMSIS DSP Library  
00008 * Title:        arm_min_q15.c  
00009 *  
00010 * Description:  Minimum value of two Q15 arrays.  
00011 *  
00012 * Target Processor: Cortex-M4/Cortex-M3
00013 *  
00014 * Version 1.0.3 2010/11/29 
00015 *    Re-organized the CMSIS folders and updated documentation.  
00016 *   
00017 * Version 1.0.2 2010/11/11  
00018 *    Documentation updated.   
00019 *  
00020 * Version 1.0.1 2010/10/05   
00021 *    Production release and review comments incorporated.  
00022 *  
00023 * Version 1.0.0 2010/09/20   
00024 *    Production release and review comments incorporated.  
00025 * ---------------------------------------------------------------------------- */ 
00026  
00027 #include "arm_math.h" 
00028  
00029 /**  
00030  * @ingroup groupStats  
00031  */ 
00032  
00033  
00034 /**  
00035  * @addtogroup Min  
00036  * @{  
00037  */ 
00038  
00039  
00040 /**  
00041  * @brief Minimum value of a Q15 vector.  
00042  * @param[in]       *pSrc points to the input vector  
00043  * @param[in]       blockSize length of the input vector  
00044  * @param[out]      *pResult minimum value returned here  
00045  * @param[out]      *pIndex index of minimum value returned here  
00046  * @return none.  
00047  *  
00048  */ 
00049  
00050 void arm_min_q15( 
00051   q15_t * pSrc, 
00052   uint32_t blockSize, 
00053   q15_t * pResult, 
00054   uint32_t * pIndex) 
00055 { 
00056   q15_t minVal, out;                             /* Temporary variables to store the output value. */ 
00057   uint32_t blkCnt, outIndex;                     /* loop counter */ 
00058  
00059   /* Initialise the index value to zero. */ 
00060   outIndex = 0u; 
00061   /* Load first input value that act as reference value for comparision */ 
00062   out = *pSrc++; 
00063  
00064   /* Loop over blockSize number of values */ 
00065   blkCnt = (blockSize - 1u); 
00066  
00067   do 
00068   { 
00069     /* Initialize minVal to the next consecutive values one by one */ 
00070     minVal = *pSrc++; 
00071  
00072     /* compare for the minimum value */ 
00073     if(out > minVal) 
00074     { 
00075       /* Update the minimum value and its index */ 
00076       out = minVal; 
00077       outIndex = blockSize - blkCnt; 
00078     } 
00079  
00080     blkCnt--; 
00081  
00082   } while(blkCnt > 0u); 
00083  
00084   /* Store the minimum value and its index into destination pointers */ 
00085   *pResult = out; 
00086   *pIndex = outIndex; 
00087 } 
00088  
00089 /**  
00090  * @} end of Min group  
00091  */