diff options
Diffstat (limited to 'fw/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c')
| -rw-r--r-- | fw/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/fw/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c new file mode 100644 index 0000000..a366f5c --- /dev/null +++ b/fw/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c @@ -0,0 +1,181 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_var_f32.c
+ * Description: Variance of the elements of a floating-point vector
+ *
+ * $Date: 27. January 2017
+ * $Revision: V.1.5.1
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupStats
+ */
+
+/**
+ * @defgroup variance Variance
+ *
+ * Calculates the variance of the elements in the input vector.
+ * The underlying algorithm used is the direct method sometimes referred to as the two-pass method:
+ *
+ * <pre>
+ * Result = sum(element - meanOfElements)^2) / numElement - 1
+ *
+ * where, meanOfElements = ( pSrc[0] * pSrc[0] + pSrc[1] * pSrc[1] + ... + pSrc[blockSize-1] ) / blockSize
+ *
+ * </pre>
+ *
+ * There are separate functions for floating point, Q31, and Q15 data types.
+ */
+
+/**
+ * @addtogroup variance
+ * @{
+ */
+
+
+/**
+ * @brief Variance of the elements of a floating-point vector.
+ * @param[in] *pSrc points to the input vector
+ * @param[in] blockSize length of the input vector
+ * @param[out] *pResult variance value returned here
+ * @return none.
+ */
+
+void arm_var_f32(
+ float32_t * pSrc,
+ uint32_t blockSize,
+ float32_t * pResult)
+{
+ float32_t fMean, fValue;
+ uint32_t blkCnt; /* loop counter */
+ float32_t * pInput = pSrc;
+ float32_t sum = 0.0f;
+ float32_t fSum = 0.0f;
+ #if defined(ARM_MATH_DSP)
+ float32_t in1, in2, in3, in4;
+ #endif
+
+ if (blockSize <= 1U)
+ {
+ *pResult = 0;
+ return;
+ }
+
+ #if defined(ARM_MATH_DSP)
+ /* Run the below code for Cortex-M4 and Cortex-M7 */
+
+ /*loop Unrolling */
+ blkCnt = blockSize >> 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 = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+ in1 = *pInput++;
+ in2 = *pInput++;
+ in3 = *pInput++;
+ in4 = *pInput++;
+
+ sum += in1;
+ sum += in2;
+ sum += in3;
+ sum += in4;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
+ ** No loop unrolling is used. */
+ blkCnt = blockSize % 0x4U;
+
+ #else
+ /* Run the below code for Cortex-M0 or Cortex-M3 */
+
+ /* Loop over blockSize number of values */
+ blkCnt = blockSize;
+
+ #endif
+
+ while (blkCnt > 0U)
+ {
+ /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+ sum += *pInput++;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */
+ fMean = sum / (float32_t) blockSize;
+
+ pInput = pSrc;
+
+ #if defined(ARM_MATH_DSP)
+
+ /*loop Unrolling */
+ blkCnt = blockSize >> 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)
+ {
+ fValue = *pInput++ - fMean;
+ fSum += fValue * fValue;
+ fValue = *pInput++ - fMean;
+ fSum += fValue * fValue;
+ fValue = *pInput++ - fMean;
+ fSum += fValue * fValue;
+ fValue = *pInput++ - fMean;
+ fSum += fValue * fValue;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ blkCnt = blockSize % 0x4U;
+ #else
+ /* Run the below code for Cortex-M0 or Cortex-M3 */
+
+ /* Loop over blockSize number of values */
+ blkCnt = blockSize;
+ #endif
+
+ while (blkCnt > 0U)
+ {
+ fValue = *pInput++ - fMean;
+ fSum += fValue * fValue;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ /* Variance */
+ *pResult = fSum / (float32_t)(blockSize - 1.0f);
+}
+
+/**
+ * @} end of variance group
+ */
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