Diff: ComplexMathFunctions/arm_cmplx_mag_squared_f32.c

Revision:

0:3d9c67d97d6f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ComplexMathFunctions/arm_cmplx_mag_squared_f32.c	Mon Jul 28 15:03:15 2014 +0000
@@ -0,0 +1,215 @@
+/* ----------------------------------------------------------------------    
+* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
+*    
+* $Date:        12. March 2014
+* $Revision: 	V1.4.3
+*    
+* Project: 	    CMSIS DSP Library    
+* Title:		arm_cmplx_mag_squared_f32.c    
+*    
+* Description:	Floating-point complex magnitude squared.    
+*    
+* 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 groupCmplxMath        
+ */
+
+/**        
+ * @defgroup cmplx_mag_squared Complex Magnitude Squared        
+ *        
+ * Computes the magnitude squared of the elements of a complex data vector.        
+ *       
+ * The <code>pSrc</code> points to the source data and        
+ * <code>pDst</code> points to the where the result should be written.        
+ * <code>numSamples</code> specifies the number of complex samples        
+ * in the input array and the data is stored in an interleaved fashion        
+ * (real, imag, real, imag, ...).        
+ * The input array has a total of <code>2*numSamples</code> values;        
+ * the output array has a total of <code>numSamples</code> values.        
+ *        
+ * The underlying algorithm is used:        
+ *        
+ * <pre>        
+ * for(n=0; n<numSamples; n++) {        
+ *     pDst[n] = pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2;        
+ * }        
+ * </pre>        
+ *        
+ * There are separate functions for floating-point, Q15, and Q31 data types.        
+ */
+
+/**        
+ * @addtogroup cmplx_mag_squared        
+ * @{        
+ */
+
+
+/**        
+ * @brief  Floating-point complex magnitude squared        
+ * @param[in]  *pSrc points to the complex input vector        
+ * @param[out]  *pDst points to the real output vector        
+ * @param[in]  numSamples number of complex samples in the input vector        
+ * @return none.        
+ */
+
+void arm_cmplx_mag_squared_f32(
+  float32_t * pSrc,
+  float32_t * pDst,
+  uint32_t numSamples)
+{
+  float32_t real, imag;                          /* Temporary variables to store real and imaginary values */
+  uint32_t blkCnt;                               /* loop counter */
+
+#ifndef ARM_MATH_CM0_FAMILY
+  float32_t real1, real2, real3, real4;          /* Temporary variables to hold real values */
+  float32_t imag1, imag2, imag3, imag4;          /* Temporary variables to hold imaginary values */
+  float32_t mul1, mul2, mul3, mul4;              /* Temporary variables */
+  float32_t mul5, mul6, mul7, mul8;              /* Temporary variables */
+  float32_t out1, out2, out3, out4;              /* Temporary variables to hold output values */
+
+  /*loop Unrolling */
+  blkCnt = numSamples >> 2u;
+
+  /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.        
+   ** a second loop below computes the remaining 1 to 3 samples. */
+  while(blkCnt > 0u)
+  {
+    /* C[0] = (A[0] * A[0] + A[1] * A[1]) */
+    /* read real input sample from source buffer */
+    real1 = pSrc[0];
+    /* read imaginary input sample from source buffer */
+    imag1 = pSrc[1];
+
+    /* calculate power of real value */
+    mul1 = real1 * real1;
+
+    /* read real input sample from source buffer */
+    real2 = pSrc[2];
+
+    /* calculate power of imaginary value */
+    mul2 = imag1 * imag1;
+
+    /* read imaginary input sample from source buffer */
+    imag2 = pSrc[3];
+
+    /* calculate power of real value */
+    mul3 = real2 * real2;
+
+    /* read real input sample from source buffer */
+    real3 = pSrc[4];
+
+    /* calculate power of imaginary value */
+    mul4 = imag2 * imag2;
+
+    /* read imaginary input sample from source buffer */
+    imag3 = pSrc[5];
+
+    /* calculate power of real value */
+    mul5 = real3 * real3;
+    /* calculate power of imaginary value */
+    mul6 = imag3 * imag3;
+
+    /* read real input sample from source buffer */
+    real4 = pSrc[6];
+
+    /* accumulate real and imaginary powers */
+    out1 = mul1 + mul2;
+
+    /* read imaginary input sample from source buffer */
+    imag4 = pSrc[7];
+
+    /* accumulate real and imaginary powers */
+    out2 = mul3 + mul4;
+
+    /* calculate power of real value */
+    mul7 = real4 * real4;
+    /* calculate power of imaginary value */
+    mul8 = imag4 * imag4;
+
+    /* store output to destination */
+    pDst[0] = out1;
+
+    /* accumulate real and imaginary powers */
+    out3 = mul5 + mul6;
+
+    /* store output to destination */
+    pDst[1] = out2;
+
+    /* accumulate real and imaginary powers */
+    out4 = mul7 + mul8;
+
+    /* store output to destination */
+    pDst[2] = out3;
+
+    /* increment destination pointer by 8 to process next samples */
+    pSrc += 8u;
+
+    /* store output to destination */
+    pDst[3] = out4;
+
+    /* increment destination pointer by 4 to process next samples */
+    pDst += 4u;
+
+    /* Decrement the loop counter */
+    blkCnt--;
+  }
+
+  /* If the numSamples is not a multiple of 4, compute any remaining output samples here.        
+   ** No loop unrolling is used. */
+  blkCnt = numSamples % 0x4u;
+
+#else
+
+  /* Run the below code for Cortex-M0 */
+
+  blkCnt = numSamples;
+
+#endif /* #ifndef ARM_MATH_CM0_FAMILY */
+
+  while(blkCnt > 0u)
+  {
+    /* C[0] = (A[0] * A[0] + A[1] * A[1]) */
+    real = *pSrc++;
+    imag = *pSrc++;
+
+    /* out = (real * real) + (imag * imag) */
+    /* store the result in the destination buffer. */
+    *pDst++ = (real * real) + (imag * imag);
+
+    /* Decrement the loop counter */
+    blkCnt--;
+  }
+}
+
+/**        
+ * @} end of cmplx_mag_squared group        
+ */