arm_min_f32.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_f32.c  
00009 *  
00010 * Description:  Minimum value of two floating point 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  * @defgroup Min Minimum  
00035  *  
00036  * Computes the minimum value of an array of data.   
00037  * The function returns both the minimum value and its position within the array.   
00038  * There are separate functions for floating-point, Q31, Q15, and Q7 data types.  
00039  */ 
00040  
00041 /**  
00042  * @addtogroup Min  
00043  * @{  
00044  */ 
00045  
00046  
00047 /**  
00048  * @brief Minimum value of a floating-point vector.  
00049  * @param[in]       *pSrc points to the input vector  
00050  * @param[in]       blockSize length of the input vector  
00051  * @param[out]      *pResult minimum value returned here  
00052  * @param[out]      *pIndex index of minimum value returned here  
00053   * @return none.  
00054  *  
00055  */ 
00056  
00057 void arm_min_f32( 
00058   float32_t * pSrc, 
00059   uint32_t blockSize, 
00060   float32_t * pResult, 
00061   uint32_t * pIndex) 
00062 { 
00063   float32_t minVal, out;                         /* Temporary variables to store the output value. */ 
00064   uint32_t blkCnt, outIndex;                     /* loop counter */ 
00065  
00066   /* Initialise the index value to zero. */ 
00067   outIndex = 0u; 
00068   /* Load first input value that act as reference value for comparision */ 
00069   out = *pSrc++; 
00070  
00071   /* Loop over blockSize number of values */ 
00072   blkCnt = (blockSize - 1u); 
00073  
00074   do 
00075   { 
00076     /* Initialize minVal to the next consecutive values one by one */ 
00077     minVal = *pSrc++; 
00078  
00079     /* compare for the minimum value */ 
00080     if(out > minVal) 
00081     { 
00082       /* Update the minimum value and it's index */ 
00083       out = minVal; 
00084       outIndex = blockSize - blkCnt; 
00085     } 
00086  
00087     blkCnt--; 
00088  
00089   } while(blkCnt > 0u); 
00090  
00091   /* Store the minimum value and it's index into destination pointers */ 
00092   *pResult = out; 
00093   *pIndex = outIndex; 
00094 } 
00095  
00096 /**  
00097  * @} end of Min group  
00098  */