From 76177aa280494bb36d7a0bcbda1078d4db717020 Mon Sep 17 00:00:00 2001 From: Ali Labbene Date: Mon, 9 Dec 2019 11:25:19 +0100 Subject: Official ARM version: v4.5 --- .../DSP/html/group__cmplx__dot__prod.html | 325 +++++++++++++++++++++ 1 file changed, 325 insertions(+) create mode 100644 Documentation/DSP/html/group__cmplx__dot__prod.html (limited to 'Documentation/DSP/html/group__cmplx__dot__prod.html') diff --git a/Documentation/DSP/html/group__cmplx__dot__prod.html b/Documentation/DSP/html/group__cmplx__dot__prod.html new file mode 100644 index 0000000..ad70f91 --- /dev/null +++ b/Documentation/DSP/html/group__cmplx__dot__prod.html @@ -0,0 +1,325 @@ + + + + + +Complex Dot Product +CMSIS-DSP: Complex Dot Product + + + + + + + + + + + + + + + +
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CMSIS-DSP +  Version 1.4.7 +
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CMSIS DSP Software Library
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+Functions
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Complex Dot Product
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Complex Math Functions
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+Functions

void arm_cmplx_dot_prod_f32 (float32_t *pSrcA, float32_t *pSrcB, uint32_t numSamples, float32_t *realResult, float32_t *imagResult)
 Floating-point complex dot product.
 
void arm_cmplx_dot_prod_q15 (q15_t *pSrcA, q15_t *pSrcB, uint32_t numSamples, q31_t *realResult, q31_t *imagResult)
 Q15 complex dot product.
 
void arm_cmplx_dot_prod_q31 (q31_t *pSrcA, q31_t *pSrcB, uint32_t numSamples, q63_t *realResult, q63_t *imagResult)
 Q31 complex dot product.
 
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Description

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Computes the dot product of two complex vectors. The vectors are multiplied element-by-element and then summed.

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The pSrcA points to the first complex input vector and pSrcB points to the second complex input vector. numSamples specifies the number of complex samples and the data in each array is stored in an interleaved fashion (real, imag, real, imag, ...). Each array has a total of 2*numSamples values.

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The underlying algorithm is used:

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+realResult=0;    
+imagResult=0;    
+for(n=0; n<numSamples; n++) {    
+    realResult += pSrcA[(2*n)+0]*pSrcB[(2*n)+0] - pSrcA[(2*n)+1]*pSrcB[(2*n)+1];    
+    imagResult += pSrcA[(2*n)+0]*pSrcB[(2*n)+1] + pSrcA[(2*n)+1]*pSrcB[(2*n)+0];    
+}    
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There are separate functions for floating-point, Q15, and Q31 data types.

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Function Documentation

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void arm_cmplx_dot_prod_f32 (float32_t * pSrcA,
float32_t * pSrcB,
uint32_t numSamples,
float32_t * realResult,
float32_t * imagResult 
)
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Parameters
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*pSrcApoints to the first input vector
*pSrcBpoints to the second input vector
numSamplesnumber of complex samples in each vector
*realResultreal part of the result returned here
*imagResultimaginary part of the result returned here
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Returns
none.
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void arm_cmplx_dot_prod_q15 (q15_t * pSrcA,
q15_t * pSrcB,
uint32_t numSamples,
q31_t * realResult,
q31_t * imagResult 
)
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Parameters
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*pSrcApoints to the first input vector
*pSrcBpoints to the second input vector
numSamplesnumber of complex samples in each vector
*realResultreal part of the result returned here
*imagResultimaginary part of the result returned here
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Returns
none.
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Scaling and Overflow Behavior:

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The function is implemented using an internal 64-bit accumulator. The intermediate 1.15 by 1.15 multiplications are performed with full precision and yield a 2.30 result. These are accumulated in a 64-bit accumulator with 34.30 precision. As a final step, the accumulators are converted to 8.24 format. The return results realResult and imagResult are in 8.24 format.
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void arm_cmplx_dot_prod_q31 (q31_t * pSrcA,
q31_t * pSrcB,
uint32_t numSamples,
q63_t * realResult,
q63_t * imagResult 
)
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Parameters
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*pSrcApoints to the first input vector
*pSrcBpoints to the second input vector
numSamplesnumber of complex samples in each vector
*realResultreal part of the result returned here
*imagResultimaginary part of the result returned here
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Returns
none.
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Scaling and Overflow Behavior:

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The function is implemented using an internal 64-bit accumulator. The intermediate 1.31 by 1.31 multiplications are performed with 64-bit precision and then shifted to 16.48 format. The internal real and imaginary accumulators are in 16.48 format and provide 15 guard bits. Additions are nonsaturating and no overflow will occur as long as numSamples is less than 32768. The return results realResult and imagResult are in 16.48 format. Input down scaling is not required.
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+ + + + -- cgit