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-rw-r--r--Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_entropy_f64.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_entropy_f64.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_entropy_f64.c
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+++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_entropy_f64.c
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+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_logsumexp_f64.c
+ * Description: LogSumExp
+ *
+ * $Date: 23 April 2021
+ * $Revision: V1.9.0
+ *
+ * Target Processor: Cortex-M and Cortex-A cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2021 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 "dsp/statistics_functions.h"
+#include <limits.h>
+#include <math.h>
+
+/**
+ * @addtogroup Entropy
+ * @{
+ */
+
+/**
+ * @brief Entropy
+ *
+ * @param[in] pSrcA Array of input values.
+ * @param[in] blockSize Number of samples in the input array.
+ * @return Entropy -Sum(p ln p)
+ *
+ */
+
+float64_t arm_entropy_f64(const float64_t * pSrcA, uint32_t blockSize)
+{
+ const float64_t *pIn;
+ uint32_t blkCnt;
+ float64_t accum, p;
+
+ pIn = pSrcA;
+ blkCnt = blockSize;
+
+ accum = 0.0;
+
+ while(blkCnt > 0)
+ {
+ p = *pIn++;
+
+ accum += p * log(p);
+
+ blkCnt--;
+
+ }
+
+ return(-accum);
+}
+
+/**
+ * @} end of Entropy group
+ */