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git.gir.st - tmk_keyboard.git/blob - tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_f32.c
1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
4 * $Date: 17. January 2013
7 * Project: CMSIS DSP Library
8 * Title: arm_cmplx_mag_f32.c
10 * Description: Floating-point complex magnitude.
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
17 * - Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * - Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in
21 * the documentation and/or other materials provided with the
23 * - Neither the name of ARM LIMITED nor the names of its contributors
24 * may be used to endorse or promote products derived from this
25 * software without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 * ---------------------------------------------------------------------------- */
44 * @ingroup groupCmplxMath
48 * @defgroup cmplx_mag Complex Magnitude
50 * Computes the magnitude of the elements of a complex data vector.
52 * The <code>pSrc</code> points to the source data and
53 * <code>pDst</code> points to the where the result should be written.
54 * <code>numSamples</code> specifies the number of complex samples
55 * in the input array and the data is stored in an interleaved fashion
56 * (real, imag, real, imag, ...).
57 * The input array has a total of <code>2*numSamples</code> values;
58 * the output array has a total of <code>numSamples</code> values.
59 * The underlying algorithm is used:
62 * for(n=0; n<numSamples; n++) {
63 * pDst[n] = sqrt(pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2);
67 * There are separate functions for floating-point, Q15, and Q31 data types.
71 * @addtogroup cmplx_mag
75 * @brief Floating-point complex magnitude.
76 * @param[in] *pSrc points to complex input buffer
77 * @param[out] *pDst points to real output buffer
78 * @param[in] numSamples number of complex samples in the input vector
84 void arm_cmplx_mag_f32(
89 float32_t realIn
, imagIn
; /* Temporary variables to hold input values */
91 #ifndef ARM_MATH_CM0_FAMILY
93 /* Run the below code for Cortex-M4 and Cortex-M3 */
94 uint32_t blkCnt
; /* loop counter */
97 blkCnt
= numSamples
>> 2u;
99 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
100 ** a second loop below computes the remaining 1 to 3 samples. */
104 /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
107 /* store the result in the destination buffer. */
108 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
112 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
116 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
120 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
123 /* Decrement the loop counter */
127 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
128 ** No loop unrolling is used. */
129 blkCnt
= numSamples
% 0x4u
;
133 /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
136 /* store the result in the destination buffer. */
137 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
139 /* Decrement the loop counter */
145 /* Run the below code for Cortex-M0 */
147 while(numSamples
> 0u)
149 /* out = sqrt((real * real) + (imag * imag)) */
152 /* store the result in the destination buffer. */
153 arm_sqrt_f32((realIn
* realIn
) + (imagIn
* imagIn
), pDst
++);
155 /* Decrement the loop counter */
159 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
164 * @} end of cmplx_mag group