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-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/CMakeLists.txt34
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctions.c41
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctionsF16.c33
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f16.c168
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f32.c161
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q15.c121
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q31.c119
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q7.c117
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f16.c132
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f32.c125
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q15.c101
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q31.c103
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q7.c99
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_f32.c283
-rw-r--r--Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_init_f32.c175
15 files changed, 1812 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/CMakeLists.txt b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/CMakeLists.txt
new file mode 100644
index 0000000..7ce79cf
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/CMakeLists.txt
@@ -0,0 +1,34 @@
+cmake_minimum_required (VERSION 3.14)
+
+project(CMSISDSPInterpolation)
+
+include(configLib)
+include(configDsp)
+
+
+add_library(CMSISDSPInterpolation STATIC)
+
+target_sources(CMSISDSPInterpolation PRIVATE arm_bilinear_interp_f32.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_bilinear_interp_q15.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_bilinear_interp_q31.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_bilinear_interp_q7.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_linear_interp_f32.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_linear_interp_q15.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_linear_interp_q31.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_linear_interp_q7.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_spline_interp_f32.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_spline_interp_init_f32.c)
+
+
+configLib(CMSISDSPInterpolation ${ROOT})
+configDsp(CMSISDSPInterpolation ${ROOT})
+
+### Includes
+target_include_directories(CMSISDSPInterpolation PUBLIC "${DSP}/Include")
+
+
+
+if ((NOT ARMAC5) AND (NOT DISABLEFLOAT16))
+target_sources(CMSISDSPInterpolation PRIVATE arm_bilinear_interp_f16.c)
+target_sources(CMSISDSPInterpolation PRIVATE arm_linear_interp_f16.c)
+endif() \ No newline at end of file
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctions.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctions.c
new file mode 100644
index 0000000..8462395
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctions.c
@@ -0,0 +1,41 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: InterpolationFunctions.c
+ * Description: Combination of all interpolation function source files.
+ *
+ * $Date: 22. July 2020
+ * $Revision: V1.0.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2020 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_bilinear_interp_f32.c"
+#include "arm_bilinear_interp_q15.c"
+#include "arm_bilinear_interp_q31.c"
+#include "arm_bilinear_interp_q7.c"
+#include "arm_linear_interp_f32.c"
+#include "arm_linear_interp_q15.c"
+#include "arm_linear_interp_q31.c"
+#include "arm_linear_interp_q7.c"
+#include "arm_spline_interp_f32.c"
+#include "arm_spline_interp_init_f32.c"
+
+
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctionsF16.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctionsF16.c
new file mode 100644
index 0000000..d778de9
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/InterpolationFunctionsF16.c
@@ -0,0 +1,33 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: InterpolationFunctions.c
+ * Description: Combination of all interpolation function source files.
+ *
+ * $Date: 22. July 2020
+ * $Revision: V1.0.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2020 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_bilinear_interp_f16.c"
+#include "arm_linear_interp_f16.c"
+
+
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f16.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f16.c
new file mode 100644
index 0000000..799ed78
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f16.c
@@ -0,0 +1,168 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_bilinear_interp_f16.c
+ * Description: Floating-point bilinear interpolation
+ *
+ * $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/interpolation_functions_f16.h"
+
+#if defined(ARM_FLOAT16_SUPPORTED)
+
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @defgroup BilinearInterpolate Bilinear Interpolation
+ *
+ * Bilinear interpolation is an extension of linear interpolation applied to a two dimensional grid.
+ * The underlying function <code>f(x, y)</code> is sampled on a regular grid and the interpolation process
+ * determines values between the grid points.
+ * Bilinear interpolation is equivalent to two step linear interpolation, first in the x-dimension and then in the y-dimension.
+ * Bilinear interpolation is often used in image processing to rescale images.
+ * The CMSIS DSP library provides bilinear interpolation functions for Q7, Q15, Q31, and floating-point data types.
+ *
+ * <b>Algorithm</b>
+ * \par
+ * The instance structure used by the bilinear interpolation functions describes a two dimensional data table.
+ * For floating-point, the instance structure is defined as:
+ * <pre>
+ * typedef struct
+ * {
+ * uint16_t numRows;
+ * uint16_t numCols;
+ * float16_t *pData;
+ * } arm_bilinear_interp_instance_f16;
+ * </pre>
+ *
+ * \par
+ * where <code>numRows</code> specifies the number of rows in the table;
+ * <code>numCols</code> specifies the number of columns in the table;
+ * and <code>pData</code> points to an array of size <code>numRows*numCols</code> values.
+ * The data table <code>pTable</code> is organized in row order and the supplied data values fall on integer indexes.
+ * That is, table element (x,y) is located at <code>pTable[x + y*numCols]</code> where x and y are integers.
+ *
+ * \par
+ * Let <code>(x, y)</code> specify the desired interpolation point. Then define:
+ * <pre>
+ * XF = floor(x)
+ * YF = floor(y)
+ * </pre>
+ * \par
+ * The interpolated output point is computed as:
+ * <pre>
+ * f(x, y) = f(XF, YF) * (1-(x-XF)) * (1-(y-YF))
+ * + f(XF+1, YF) * (x-XF)*(1-(y-YF))
+ * + f(XF, YF+1) * (1-(x-XF))*(y-YF)
+ * + f(XF+1, YF+1) * (x-XF)*(y-YF)
+ * </pre>
+ * Note that the coordinates (x, y) contain integer and fractional components.
+ * The integer components specify which portion of the table to use while the
+ * fractional components control the interpolation processor.
+ *
+ * \par
+ * if (x,y) are outside of the table boundary, Bilinear interpolation returns zero output.
+ */
+
+
+ /**
+ * @addtogroup BilinearInterpolate
+ * @{
+ */
+
+
+ /**
+ * @brief Floating-point bilinear interpolation.
+ * @param[in,out] S points to an instance of the interpolation structure.
+ * @param[in] X interpolation coordinate.
+ * @param[in] Y interpolation coordinate.
+ * @return out interpolated value.
+ */
+ float16_t arm_bilinear_interp_f16(
+ const arm_bilinear_interp_instance_f16 * S,
+ float16_t X,
+ float16_t Y)
+ {
+ float16_t out;
+ float16_t f00, f01, f10, f11;
+ float16_t *pData = S->pData;
+ int32_t xIndex, yIndex, index;
+ float16_t xdiff, ydiff;
+ float16_t b1, b2, b3, b4;
+
+ xIndex = (int32_t) X;
+ yIndex = (int32_t) Y;
+
+ /* Care taken for table outside boundary */
+ /* Returns zero output when values are outside table boundary */
+ if (xIndex < 0 || xIndex > (S->numCols - 2) || yIndex < 0 || yIndex > (S->numRows - 2))
+ {
+ return (0);
+ }
+
+ /* Calculation of index for two nearest points in X-direction */
+ index = (xIndex ) + (yIndex ) * S->numCols;
+
+
+ /* Read two nearest points in X-direction */
+ f00 = pData[index];
+ f01 = pData[index + 1];
+
+ /* Calculation of index for two nearest points in Y-direction */
+ index = (xIndex ) + (yIndex+1) * S->numCols;
+
+
+ /* Read two nearest points in Y-direction */
+ f10 = pData[index];
+ f11 = pData[index + 1];
+
+ /* Calculation of intermediate values */
+ b1 = f00;
+ b2 = (_Float16)f01 - (_Float16)f00;
+ b3 = (_Float16)f10 - (_Float16)f00;
+ b4 = (_Float16)f00 - (_Float16)f01 - (_Float16)f10 + (_Float16)f11;
+
+ /* Calculation of fractional part in X */
+ xdiff = (_Float16)X - (_Float16)xIndex;
+
+ /* Calculation of fractional part in Y */
+ ydiff = (_Float16)Y - (_Float16)yIndex;
+
+ /* Calculation of bi-linear interpolated output */
+ out = (_Float16)b1 + (_Float16)b2 * (_Float16)xdiff +
+ (_Float16)b3 * (_Float16)ydiff + (_Float16)b4 * (_Float16)xdiff * (_Float16)ydiff;
+
+ /* return to application */
+ return (out);
+ }
+
+ /**
+ * @} end of BilinearInterpolate group
+ */
+
+
+#endif /* #if defined(ARM_FLOAT16_SUPPORTED) */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f32.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f32.c
new file mode 100644
index 0000000..fc001d7
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_f32.c
@@ -0,0 +1,161 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_bilinear_interp_f32.c
+ * Description: Floating-point bilinear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @defgroup BilinearInterpolate Bilinear Interpolation
+ *
+ * Bilinear interpolation is an extension of linear interpolation applied to a two dimensional grid.
+ * The underlying function <code>f(x, y)</code> is sampled on a regular grid and the interpolation process
+ * determines values between the grid points.
+ * Bilinear interpolation is equivalent to two step linear interpolation, first in the x-dimension and then in the y-dimension.
+ * Bilinear interpolation is often used in image processing to rescale images.
+ * The CMSIS DSP library provides bilinear interpolation functions for Q7, Q15, Q31, and floating-point data types.
+ *
+ * <b>Algorithm</b>
+ * \par
+ * The instance structure used by the bilinear interpolation functions describes a two dimensional data table.
+ * For floating-point, the instance structure is defined as:
+ * <pre>
+ * typedef struct
+ * {
+ * uint16_t numRows;
+ * uint16_t numCols;
+ * float32_t *pData;
+ * } arm_bilinear_interp_instance_f32;
+ * </pre>
+ *
+ * \par
+ * where <code>numRows</code> specifies the number of rows in the table;
+ * <code>numCols</code> specifies the number of columns in the table;
+ * and <code>pData</code> points to an array of size <code>numRows*numCols</code> values.
+ * The data table <code>pTable</code> is organized in row order and the supplied data values fall on integer indexes.
+ * That is, table element (x,y) is located at <code>pTable[x + y*numCols]</code> where x and y are integers.
+ *
+ * \par
+ * Let <code>(x, y)</code> specify the desired interpolation point. Then define:
+ * <pre>
+ * XF = floor(x)
+ * YF = floor(y)
+ * </pre>
+ * \par
+ * The interpolated output point is computed as:
+ * <pre>
+ * f(x, y) = f(XF, YF) * (1-(x-XF)) * (1-(y-YF))
+ * + f(XF+1, YF) * (x-XF)*(1-(y-YF))
+ * + f(XF, YF+1) * (1-(x-XF))*(y-YF)
+ * + f(XF+1, YF+1) * (x-XF)*(y-YF)
+ * </pre>
+ * Note that the coordinates (x, y) contain integer and fractional components.
+ * The integer components specify which portion of the table to use while the
+ * fractional components control the interpolation processor.
+ *
+ * \par
+ * if (x,y) are outside of the table boundary, Bilinear interpolation returns zero output.
+ */
+
+
+ /**
+ * @addtogroup BilinearInterpolate
+ * @{
+ */
+
+
+ /**
+ * @brief Floating-point bilinear interpolation.
+ * @param[in,out] S points to an instance of the interpolation structure.
+ * @param[in] X interpolation coordinate.
+ * @param[in] Y interpolation coordinate.
+ * @return out interpolated value.
+ */
+ float32_t arm_bilinear_interp_f32(
+ const arm_bilinear_interp_instance_f32 * S,
+ float32_t X,
+ float32_t Y)
+ {
+ float32_t out;
+ float32_t f00, f01, f10, f11;
+ float32_t *pData = S->pData;
+ int32_t xIndex, yIndex, index;
+ float32_t xdiff, ydiff;
+ float32_t b1, b2, b3, b4;
+
+ xIndex = (int32_t) X;
+ yIndex = (int32_t) Y;
+
+ /* Care taken for table outside boundary */
+ /* Returns zero output when values are outside table boundary */
+ if (xIndex < 0 || xIndex > (S->numCols - 2) || yIndex < 0 || yIndex > (S->numRows - 2))
+ {
+ return (0);
+ }
+
+ /* Calculation of index for two nearest points in X-direction */
+ index = (xIndex ) + (yIndex ) * S->numCols;
+
+
+ /* Read two nearest points in X-direction */
+ f00 = pData[index];
+ f01 = pData[index + 1];
+
+ /* Calculation of index for two nearest points in Y-direction */
+ index = (xIndex ) + (yIndex+1) * S->numCols;
+
+
+ /* Read two nearest points in Y-direction */
+ f10 = pData[index];
+ f11 = pData[index + 1];
+
+ /* Calculation of intermediate values */
+ b1 = f00;
+ b2 = f01 - f00;
+ b3 = f10 - f00;
+ b4 = f00 - f01 - f10 + f11;
+
+ /* Calculation of fractional part in X */
+ xdiff = X - xIndex;
+
+ /* Calculation of fractional part in Y */
+ ydiff = Y - yIndex;
+
+ /* Calculation of bi-linear interpolated output */
+ out = b1 + b2 * xdiff + b3 * ydiff + b4 * xdiff * ydiff;
+
+ /* return to application */
+ return (out);
+ }
+
+ /**
+ * @} end of BilinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q15.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q15.c
new file mode 100644
index 0000000..6726736
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q15.c
@@ -0,0 +1,121 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q15.c
+ * Description: Q15 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @addtogroup BilinearInterpolate
+ * @{
+ */
+
+ /**
+ * @brief Q15 bilinear interpolation.
+ * @param[in,out] S points to an instance of the interpolation structure.
+ * @param[in] X interpolation coordinate in 12.20 format.
+ * @param[in] Y interpolation coordinate in 12.20 format.
+ * @return out interpolated value.
+ */
+ q15_t arm_bilinear_interp_q15(
+ arm_bilinear_interp_instance_q15 * S,
+ q31_t X,
+ q31_t Y)
+ {
+ q63_t acc = 0; /* output */
+ q31_t out; /* Temporary output */
+ q15_t x1, x2, y1, y2; /* Nearest output values */
+ q31_t xfract, yfract; /* X, Y fractional parts */
+ int32_t rI, cI; /* Row and column indices */
+ q15_t *pYData = S->pData; /* pointer to output table values */
+ uint32_t nCols = S->numCols; /* num of rows */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ rI = ((X & (q31_t)0xFFF00000) >> 20);
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ cI = ((Y & (q31_t)0xFFF00000) >> 20);
+
+ /* Care taken for table outside boundary */
+ /* Returns zero output when values are outside table boundary */
+ if (rI < 0 || rI > (S->numCols - 2) || cI < 0 || cI > (S->numRows - 2))
+ {
+ return (0);
+ }
+
+ /* 20 bits for the fractional part */
+ /* xfract should be in 12.20 format */
+ xfract = (X & 0x000FFFFF);
+
+ /* Read two nearest output values from the index */
+ x1 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI) ];
+ x2 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI) + 1];
+
+ /* 20 bits for the fractional part */
+ /* yfract should be in 12.20 format */
+ yfract = (Y & 0x000FFFFF);
+
+ /* Read two nearest output values from the index */
+ y1 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI + 1) ];
+ y2 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI + 1) + 1];
+
+ /* Calculation of x1 * (1-xfract ) * (1-yfract) and acc is in 13.51 format */
+
+ /* x1 is in 1.15(q15), xfract in 12.20 format and out is in 13.35 format */
+ /* convert 13.35 to 13.31 by right shifting and out is in 1.31 */
+ out = (q31_t) (((q63_t) x1 * (0x0FFFFF - xfract)) >> 4U);
+ acc = ((q63_t) out * (0x0FFFFF - yfract));
+
+ /* x2 * (xfract) * (1-yfract) in 1.51 and adding to acc */
+ out = (q31_t) (((q63_t) x2 * (0x0FFFFF - yfract)) >> 4U);
+ acc += ((q63_t) out * (xfract));
+
+ /* y1 * (1 - xfract) * (yfract) in 1.51 and adding to acc */
+ out = (q31_t) (((q63_t) y1 * (0x0FFFFF - xfract)) >> 4U);
+ acc += ((q63_t) out * (yfract));
+
+ /* y2 * (xfract) * (yfract) in 1.51 and adding to acc */
+ out = (q31_t) (((q63_t) y2 * (xfract)) >> 4U);
+ acc += ((q63_t) out * (yfract));
+
+ /* acc is in 13.51 format and down shift acc by 36 times */
+ /* Convert out to 1.15 format */
+ return ((q15_t)(acc >> 36));
+ }
+
+
+ /**
+ * @} end of BilinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q31.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q31.c
new file mode 100644
index 0000000..cc8560e
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q31.c
@@ -0,0 +1,119 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q31.c
+ * Description: Q31 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+
+/**
+ * @addtogroup BilinearInterpolate
+ * @{
+ */
+
+ /**
+ * @brief Q31 bilinear interpolation.
+ * @param[in,out] S points to an instance of the interpolation structure.
+ * @param[in] X interpolation coordinate in 12.20 format.
+ * @param[in] Y interpolation coordinate in 12.20 format.
+ * @return out interpolated value.
+ */
+ q31_t arm_bilinear_interp_q31(
+ arm_bilinear_interp_instance_q31 * S,
+ q31_t X,
+ q31_t Y)
+ {
+ q31_t out; /* Temporary output */
+ q31_t acc = 0; /* output */
+ q31_t xfract, yfract; /* X, Y fractional parts */
+ q31_t x1, x2, y1, y2; /* Nearest output values */
+ int32_t rI, cI; /* Row and column indices */
+ q31_t *pYData = S->pData; /* pointer to output table values */
+ uint32_t nCols = S->numCols; /* num of rows */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ rI = ((X & (q31_t)0xFFF00000) >> 20);
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ cI = ((Y & (q31_t)0xFFF00000) >> 20);
+
+ /* Care taken for table outside boundary */
+ /* Returns zero output when values are outside table boundary */
+ if (rI < 0 || rI > (S->numCols - 2) || cI < 0 || cI > (S->numRows - 2))
+ {
+ return (0);
+ }
+
+ /* 20 bits for the fractional part */
+ /* shift left xfract by 11 to keep 1.31 format */
+ xfract = (X & 0x000FFFFF) << 11U;
+
+ /* Read two nearest output values from the index */
+ x1 = pYData[(rI) + (int32_t)nCols * (cI) ];
+ x2 = pYData[(rI) + (int32_t)nCols * (cI) + 1];
+
+ /* 20 bits for the fractional part */
+ /* shift left yfract by 11 to keep 1.31 format */
+ yfract = (Y & 0x000FFFFF) << 11U;
+
+ /* Read two nearest output values from the index */
+ y1 = pYData[(rI) + (int32_t)nCols * (cI + 1) ];
+ y2 = pYData[(rI) + (int32_t)nCols * (cI + 1) + 1];
+
+ /* Calculation of x1 * (1-xfract ) * (1-yfract) and acc is in 3.29(q29) format */
+ out = ((q31_t) (((q63_t) x1 * (0x7FFFFFFF - xfract)) >> 32));
+ acc = ((q31_t) (((q63_t) out * (0x7FFFFFFF - yfract)) >> 32));
+
+ /* x2 * (xfract) * (1-yfract) in 3.29(q29) and adding to acc */
+ out = ((q31_t) ((q63_t) x2 * (0x7FFFFFFF - yfract) >> 32));
+ acc += ((q31_t) ((q63_t) out * (xfract) >> 32));
+
+ /* y1 * (1 - xfract) * (yfract) in 3.29(q29) and adding to acc */
+ out = ((q31_t) ((q63_t) y1 * (0x7FFFFFFF - xfract) >> 32));
+ acc += ((q31_t) ((q63_t) out * (yfract) >> 32));
+
+ /* y2 * (xfract) * (yfract) in 3.29(q29) and adding to acc */
+ out = ((q31_t) ((q63_t) y2 * (xfract) >> 32));
+ acc += ((q31_t) ((q63_t) out * (yfract) >> 32));
+
+ /* Convert acc to 1.31(q31) format */
+ return ((q31_t)(acc << 2));
+ }
+
+
+
+ /**
+ * @} end of BilinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q7.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q7.c
new file mode 100644
index 0000000..204342e
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_bilinear_interp_q7.c
@@ -0,0 +1,117 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q7.c
+ * Description: Q7 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+
+/**
+ * @addtogroup BilinearInterpolate
+ * @{
+ */
+
+/**
+ * @brief Q7 bilinear interpolation.
+ * @param[in,out] S points to an instance of the interpolation structure.
+ * @param[in] X interpolation coordinate in 12.20 format.
+ * @param[in] Y interpolation coordinate in 12.20 format.
+ * @return out interpolated value.
+ */
+ q7_t arm_bilinear_interp_q7(
+ arm_bilinear_interp_instance_q7 * S,
+ q31_t X,
+ q31_t Y)
+ {
+ q63_t acc = 0; /* output */
+ q31_t out; /* Temporary output */
+ q31_t xfract, yfract; /* X, Y fractional parts */
+ q7_t x1, x2, y1, y2; /* Nearest output values */
+ int32_t rI, cI; /* Row and column indices */
+ q7_t *pYData = S->pData; /* pointer to output table values */
+ uint32_t nCols = S->numCols; /* num of rows */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ rI = ((X & (q31_t)0xFFF00000) >> 20);
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ cI = ((Y & (q31_t)0xFFF00000) >> 20);
+
+ /* Care taken for table outside boundary */
+ /* Returns zero output when values are outside table boundary */
+ if (rI < 0 || rI > (S->numCols - 2) || cI < 0 || cI > (S->numRows - 2))
+ {
+ return (0);
+ }
+
+ /* 20 bits for the fractional part */
+ /* xfract should be in 12.20 format */
+ xfract = (X & (q31_t)0x000FFFFF);
+
+ /* Read two nearest output values from the index */
+ x1 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI) ];
+ x2 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI) + 1];
+
+ /* 20 bits for the fractional part */
+ /* yfract should be in 12.20 format */
+ yfract = (Y & (q31_t)0x000FFFFF);
+
+ /* Read two nearest output values from the index */
+ y1 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI + 1) ];
+ y2 = pYData[((uint32_t)rI) + nCols * ((uint32_t)cI + 1) + 1];
+
+ /* Calculation of x1 * (1-xfract ) * (1-yfract) and acc is in 16.47 format */
+ out = ((x1 * (0xFFFFF - xfract)));
+ acc = (((q63_t) out * (0xFFFFF - yfract)));
+
+ /* x2 * (xfract) * (1-yfract) in 2.22 and adding to acc */
+ out = ((x2 * (0xFFFFF - yfract)));
+ acc += (((q63_t) out * (xfract)));
+
+ /* y1 * (1 - xfract) * (yfract) in 2.22 and adding to acc */
+ out = ((y1 * (0xFFFFF - xfract)));
+ acc += (((q63_t) out * (yfract)));
+
+ /* y2 * (xfract) * (yfract) in 2.22 and adding to acc */
+ out = ((y2 * (yfract)));
+ acc += (((q63_t) out * (xfract)));
+
+ /* acc in 16.47 format and down shift by 40 to convert to 1.7 format */
+ return ((q7_t)(acc >> 40));
+ }
+
+ /**
+ * @} end of BilinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f16.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f16.c
new file mode 100644
index 0000000..f4ae1e1
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f16.c
@@ -0,0 +1,132 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_f16.c
+ * Description: Floating-point linear interpolation
+ *
+ * $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/interpolation_functions_f16.h"
+
+#if defined(ARM_FLOAT16_SUPPORTED)
+
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @defgroup LinearInterpolate Linear Interpolation
+ *
+ * Linear interpolation is a method of curve fitting using linear polynomials.
+ * Linear interpolation works by effectively drawing a straight line between two neighboring samples and returning the appropriate point along that line
+ *
+ * \par
+ * \image html LinearInterp.gif "Linear interpolation"
+ *
+ * \par
+ * A Linear Interpolate function calculates an output value(y), for the input(x)
+ * using linear interpolation of the input values x0, x1( nearest input values) and the output values y0 and y1(nearest output values)
+ *
+ * \par Algorithm:
+ * <pre>
+ * y = y0 + (x - x0) * ((y1 - y0)/(x1-x0))
+ * where x0, x1 are nearest values of input x
+ * y0, y1 are nearest values to output y
+ * </pre>
+ *
+ * \par
+ * This set of functions implements Linear interpolation process
+ * for Q7, Q15, Q31, and floating-point data types. The functions operate on a single
+ * sample of data and each call to the function returns a single processed value.
+ * <code>S</code> points to an instance of the Linear Interpolate function data structure.
+ * <code>x</code> is the input sample value. The functions returns the output value.
+ *
+ * \par
+ * if x is outside of the table boundary, Linear interpolation returns first value of the table
+ * if x is below input range and returns last value of table if x is above range.
+ */
+
+/**
+ * @addtogroup LinearInterpolate
+ * @{
+ */
+
+ /**
+ * @brief Process function for the floating-point Linear Interpolation Function.
+ * @param[in,out] S is an instance of the floating-point Linear Interpolation structure
+ * @param[in] x input sample to process
+ * @return y processed output sample.
+ *
+ */
+ float16_t arm_linear_interp_f16(
+ arm_linear_interp_instance_f16 * S,
+ float16_t x)
+ {
+ float16_t y;
+ float16_t x0, x1; /* Nearest input values */
+ float16_t y0, y1; /* Nearest output values */
+ float16_t xSpacing = S->xSpacing; /* spacing between input values */
+ int32_t i; /* Index variable */
+ float16_t *pYData = S->pYData; /* pointer to output table */
+
+ /* Calculation of index */
+ i = (int32_t) (((_Float16)x - (_Float16)S->x1) / (_Float16)xSpacing);
+
+ if (i < 0)
+ {
+ /* Iniatilize output for below specified range as least output value of table */
+ y = pYData[0];
+ }
+ else if ((uint32_t)i >= (S->nValues - 1))
+ {
+ /* Iniatilize output for above specified range as last output value of table */
+ y = pYData[S->nValues - 1];
+ }
+ else
+ {
+ /* Calculation of nearest input values */
+ x0 = (_Float16)S->x1 + (_Float16)i * (_Float16)xSpacing;
+ x1 = (_Float16)S->x1 + (_Float16)(i + 1) * (_Float16)xSpacing;
+
+ /* Read of nearest output values */
+ y0 = pYData[i];
+ y1 = pYData[i + 1];
+
+ /* Calculation of output */
+ y = (_Float16)y0 + ((_Float16)x - (_Float16)x0) *
+ (((_Float16)y1 - (_Float16)y0) / ((_Float16)x1 - (_Float16)x0));
+
+ }
+
+ /* returns output value */
+ return (y);
+ }
+
+ /**
+ * @} end of LinearInterpolate group
+ */
+
+
+#endif /* #if defined(ARM_FLOAT16_SUPPORTED) */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f32.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f32.c
new file mode 100644
index 0000000..fc60bec
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_f32.c
@@ -0,0 +1,125 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_f32.c
+ * Description: Floating-point linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @defgroup LinearInterpolate Linear Interpolation
+ *
+ * Linear interpolation is a method of curve fitting using linear polynomials.
+ * Linear interpolation works by effectively drawing a straight line between two neighboring samples and returning the appropriate point along that line
+ *
+ * \par
+ * \image html LinearInterp.gif "Linear interpolation"
+ *
+ * \par
+ * A Linear Interpolate function calculates an output value(y), for the input(x)
+ * using linear interpolation of the input values x0, x1( nearest input values) and the output values y0 and y1(nearest output values)
+ *
+ * \par Algorithm:
+ * <pre>
+ * y = y0 + (x - x0) * ((y1 - y0)/(x1-x0))
+ * where x0, x1 are nearest values of input x
+ * y0, y1 are nearest values to output y
+ * </pre>
+ *
+ * \par
+ * This set of functions implements Linear interpolation process
+ * for Q7, Q15, Q31, and floating-point data types. The functions operate on a single
+ * sample of data and each call to the function returns a single processed value.
+ * <code>S</code> points to an instance of the Linear Interpolate function data structure.
+ * <code>x</code> is the input sample value. The functions returns the output value.
+ *
+ * \par
+ * if x is outside of the table boundary, Linear interpolation returns first value of the table
+ * if x is below input range and returns last value of table if x is above range.
+ */
+
+/**
+ * @addtogroup LinearInterpolate
+ * @{
+ */
+
+ /**
+ * @brief Process function for the floating-point Linear Interpolation Function.
+ * @param[in,out] S is an instance of the floating-point Linear Interpolation structure
+ * @param[in] x input sample to process
+ * @return y processed output sample.
+ *
+ */
+ float32_t arm_linear_interp_f32(
+ arm_linear_interp_instance_f32 * S,
+ float32_t x)
+ {
+ float32_t y;
+ float32_t x0, x1; /* Nearest input values */
+ float32_t y0, y1; /* Nearest output values */
+ float32_t xSpacing = S->xSpacing; /* spacing between input values */
+ int32_t i; /* Index variable */
+ float32_t *pYData = S->pYData; /* pointer to output table */
+
+ /* Calculation of index */
+ i = (int32_t) ((x - S->x1) / xSpacing);
+
+ if (i < 0)
+ {
+ /* Iniatilize output for below specified range as least output value of table */
+ y = pYData[0];
+ }
+ else if ((uint32_t)i >= (S->nValues - 1))
+ {
+ /* Iniatilize output for above specified range as last output value of table */
+ y = pYData[S->nValues - 1];
+ }
+ else
+ {
+ /* Calculation of nearest input values */
+ x0 = S->x1 + i * xSpacing;
+ x1 = S->x1 + (i + 1) * xSpacing;
+
+ /* Read of nearest output values */
+ y0 = pYData[i];
+ y1 = pYData[i + 1];
+
+ /* Calculation of output */
+ y = y0 + (x - x0) * ((y1 - y0) / (x1 - x0));
+
+ }
+
+ /* returns output value */
+ return (y);
+ }
+
+ /**
+ * @} end of LinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q15.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q15.c
new file mode 100644
index 0000000..e6339f3
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q15.c
@@ -0,0 +1,101 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q15.c
+ * Description: Q15 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ * @addtogroup LinearInterpolate
+ * @{
+ */
+
+ /**
+ *
+ * @brief Process function for the Q15 Linear Interpolation Function.
+ * @param[in] pYData pointer to Q15 Linear Interpolation table
+ * @param[in] x input sample to process
+ * @param[in] nValues number of table values
+ * @return y processed output sample.
+ *
+ * \par
+ * Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part.
+ * This function can support maximum of table size 2^12.
+ *
+ */
+ q15_t arm_linear_interp_q15(
+ const q15_t * pYData,
+ q31_t x,
+ uint32_t nValues)
+ {
+ q63_t y; /* output */
+ q15_t y0, y1; /* Nearest output values */
+ q31_t fract; /* fractional part */
+ int32_t index; /* Index to read nearest output values */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ index = ((x & (int32_t)0xFFF00000) >> 20);
+
+ if (index >= (int32_t)(nValues - 1))
+ {
+ return (pYData[nValues - 1]);
+ }
+ else if (index < 0)
+ {
+ return (pYData[0]);
+ }
+ else
+ {
+ /* 20 bits for the fractional part */
+ /* fract is in 12.20 format */
+ fract = (x & 0x000FFFFF);
+
+ /* Read two nearest output values from the index */
+ y0 = pYData[index];
+ y1 = pYData[index + 1];
+
+ /* Calculation of y0 * (1-fract) and y is in 13.35 format */
+ y = ((q63_t) y0 * (0xFFFFF - fract));
+
+ /* Calculation of (y0 * (1-fract) + y1 * fract) and y is in 13.35 format */
+ y += ((q63_t) y1 * (fract));
+
+ /* convert y to 1.15 format */
+ return (q15_t) (y >> 20);
+ }
+ }
+
+
+ /**
+ * @} end of LinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q31.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q31.c
new file mode 100644
index 0000000..f0c7560
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q31.c
@@ -0,0 +1,103 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q31.c
+ * Description: Q31 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+
+/**
+ * @addtogroup LinearInterpolate
+ * @{
+ */
+
+ /**
+ *
+ * @brief Process function for the Q31 Linear Interpolation Function.
+ * @param[in] pYData pointer to Q31 Linear Interpolation table
+ * @param[in] x input sample to process
+ * @param[in] nValues number of table values
+ * @return y processed output sample.
+ *
+ * \par
+ * Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part.
+ * This function can support maximum of table size 2^12.
+ *
+ */
+ q31_t arm_linear_interp_q31(
+ const q31_t * pYData,
+ q31_t x,
+ uint32_t nValues)
+ {
+ q31_t y; /* output */
+ q31_t y0, y1; /* Nearest output values */
+ q31_t fract; /* fractional part */
+ int32_t index; /* Index to read nearest output values */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ index = ((x & (q31_t)0xFFF00000) >> 20);
+
+ if (index >= (int32_t)(nValues - 1))
+ {
+ return (pYData[nValues - 1]);
+ }
+ else if (index < 0)
+ {
+ return (pYData[0]);
+ }
+ else
+ {
+ /* 20 bits for the fractional part */
+ /* shift left by 11 to keep fract in 1.31 format */
+ fract = (x & 0x000FFFFF) << 11;
+
+ /* Read two nearest output values from the index in 1.31(q31) format */
+ y0 = pYData[index];
+ y1 = pYData[index + 1];
+
+ /* Calculation of y0 * (1-fract) and y is in 2.30 format */
+ y = ((q31_t) ((q63_t) y0 * (0x7FFFFFFF - fract) >> 32));
+
+ /* Calculation of y0 * (1-fract) + y1 *fract and y is in 2.30 format */
+ y += ((q31_t) (((q63_t) y1 * fract) >> 32));
+
+ /* Convert y to 1.31 format */
+ return (y << 1U);
+ }
+ }
+
+
+
+ /**
+ * @} end of LinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q7.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q7.c
new file mode 100644
index 0000000..8d15432
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_linear_interp_q7.c
@@ -0,0 +1,99 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_linear_interp_q7.c
+ * Description: Q7 linear interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+
+/**
+ * @addtogroup LinearInterpolate
+ * @{
+ */
+
+ /**
+ *
+ * @brief Process function for the Q7 Linear Interpolation Function.
+ * @param[in] pYData pointer to Q7 Linear Interpolation table
+ * @param[in] x input sample to process
+ * @param[in] nValues number of table values
+ * @return y processed output sample.
+ *
+ * \par
+ * Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part.
+ * This function can support maximum of table size 2^12.
+ */
+ q7_t arm_linear_interp_q7(
+ const q7_t * pYData,
+ q31_t x,
+ uint32_t nValues)
+ {
+ q31_t y; /* output */
+ q7_t y0, y1; /* Nearest output values */
+ q31_t fract; /* fractional part */
+ uint32_t index; /* Index to read nearest output values */
+
+ /* Input is in 12.20 format */
+ /* 12 bits for the table index */
+ /* Index value calculation */
+ if (x < 0)
+ {
+ return (pYData[0]);
+ }
+ index = (x >> 20) & 0xfff;
+
+ if (index >= (nValues - 1))
+ {
+ return (pYData[nValues - 1]);
+ }
+ else
+ {
+ /* 20 bits for the fractional part */
+ /* fract is in 12.20 format */
+ fract = (x & 0x000FFFFF);
+
+ /* Read two nearest output values from the index and are in 1.7(q7) format */
+ y0 = pYData[index];
+ y1 = pYData[index + 1];
+
+ /* Calculation of y0 * (1-fract ) and y is in 13.27(q27) format */
+ y = ((y0 * (0xFFFFF - fract)));
+
+ /* Calculation of y1 * fract + y0 * (1-fract) and y is in 13.27(q27) format */
+ y += (y1 * fract);
+
+ /* convert y to 1.7(q7) format */
+ return (q7_t) (y >> 20);
+ }
+ }
+ /**
+ * @} end of LinearInterpolate group
+ */
+
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_f32.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_f32.c
new file mode 100644
index 0000000..3e3d091
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_f32.c
@@ -0,0 +1,283 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_spline_interp_f32.c
+ * Description: Floating-point cubic spline interpolation
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ @defgroup SplineInterpolate Cubic Spline Interpolation
+
+ Spline interpolation is a method of interpolation where the interpolant
+ is a piecewise-defined polynomial called "spline".
+
+ @par Introduction
+
+ Given a function f defined on the interval [a,b], a set of n nodes x(i)
+ where a=x(1)<x(2)<...<x(n)=b and a set of n values y(i) = f(x(i)),
+ a cubic spline interpolant S(x) is defined as:
+
+ <pre>
+ S1(x) x(1) < x < x(2)
+ S(x) = ...
+ Sn-1(x) x(n-1) < x < x(n)
+ </pre>
+
+ where
+
+ <pre>
+ Si(x) = a_i+b_i(x-xi)+c_i(x-xi)^2+d_i(x-xi)^3 i=1, ..., n-1
+ </pre>
+
+ @par Algorithm
+
+ Having defined h(i) = x(i+1) - x(i)
+
+ <pre>
+ h(i-1)c(i-1)+2[h(i-1)+h(i)]c(i)+h(i)c(i+1) = 3/h(i)*[a(i+1)-a(i)]-3/h(i-1)*[a(i)-a(i-1)] i=2, ..., n-1
+ </pre>
+
+ It is possible to write the previous conditions in matrix form (Ax=B).
+ In order to solve the system two boundary conidtions are needed.
+ - Natural spline: S1''(x1)=2*c(1)=0 ; Sn''(xn)=2*c(n)=0
+ In matrix form:
+
+ <pre>
+ | 1 0 0 ... 0 0 0 || c(1) | | 0 |
+ | h(0) 2[h(0)+h(1)] h(1) ... 0 0 0 || c(2) | | 3/h(2)*[a(3)-a(2)]-3/h(1)*[a(2)-a(1)] |
+ | ... ... ... ... ... ... ... || ... |=| ... |
+ | 0 0 0 ... h(n-2) 2[h(n-2)+h(n-1)] h(n-1) || c(n-1) | | 3/h(n-1)*[a(n)-a(n-1)]-3/h(n-2)*[a(n-1)-a(n-2)] |
+ | 0 0 0 ... 0 0 1 || c(n) | | 0 |
+ </pre>
+
+ - Parabolic runout spline: S1''(x1)=2*c(1)=S2''(x2)=2*c(2) ; Sn-1''(xn-1)=2*c(n-1)=Sn''(xn)=2*c(n)
+ In matrix form:
+
+ <pre>
+ | 1 -1 0 ... 0 0 0 || c(1) | | 0 |
+ | h(0) 2[h(0)+h(1)] h(1) ... 0 0 0 || c(2) | | 3/h(2)*[a(3)-a(2)]-3/h(1)*[a(2)-a(1)] |
+ | ... ... ... ... ... ... ... || ... |=| ... |
+ | 0 0 0 ... h(n-2) 2[h(n-2)+h(n-1)] h(n-1) || c(n-1) | | 3/h(n-1)*[a(n)-a(n-1)]-3/h(n-2)*[a(n-1)-a(n-2)] |
+ | 0 0 0 ... 0 -1 1 || c(n) | | 0 |
+ </pre>
+
+ A is a tridiagonal matrix (a band matrix of bandwidth 3) of size N=n+1. The factorization
+ algorithms (A=LU) can be simplified considerably because a large number of zeros appear
+ in regular patterns. The Crout method has been used:
+ 1) Solve LZ=B
+
+ <pre>
+ u(1,2) = A(1,2)/A(1,1)
+ z(1) = B(1)/l(11)
+
+ FOR i=2, ..., N-1
+ l(i,i) = A(i,i)-A(i,i-1)u(i-1,i)
+ u(i,i+1) = a(i,i+1)/l(i,i)
+ z(i) = [B(i)-A(i,i-1)z(i-1)]/l(i,i)
+
+ l(N,N) = A(N,N)-A(N,N-1)u(N-1,N)
+ z(N) = [B(N)-A(N,N-1)z(N-1)]/l(N,N)
+ </pre>
+
+ 2) Solve UX=Z
+
+ <pre>
+ c(N)=z(N)
+
+ FOR i=N-1, ..., 1
+ c(i)=z(i)-u(i,i+1)c(i+1)
+ </pre>
+
+ c(i) for i=1, ..., n-1 are needed to compute the n-1 polynomials.
+ b(i) and d(i) are computed as:
+ - b(i) = [y(i+1)-y(i)]/h(i)-h(i)*[c(i+1)+2*c(i)]/3
+ - d(i) = [c(i+1)-c(i)]/[3*h(i)]
+ Moreover, a(i)=y(i).
+
+ @par Behaviour outside the given intervals
+
+ It is possible to compute the interpolated vector for x values outside the
+ input range (xq<x(1); xq>x(n)). The coefficients used to compute the y values for
+ xq<x(1) are going to be the ones used for the first interval, while for xq>x(n) the
+ coefficients used for the last interval.
+
+ */
+
+/**
+ @addtogroup SplineInterpolate
+ @{
+ */
+
+/**
+ * @brief Processing function for the floating-point cubic spline interpolation.
+ * @param[in] S points to an instance of the floating-point spline structure.
+ * @param[in] xq points to the x values of the interpolated data points.
+ * @param[out] pDst points to the block of output data.
+ * @param[in] blockSize number of samples of output data.
+ */
+
+void arm_spline_f32(
+ arm_spline_instance_f32 * S,
+ const float32_t * xq,
+ float32_t * pDst,
+ uint32_t blockSize)
+{
+ const float32_t * x = S->x;
+ const float32_t * y = S->y;
+ int32_t n = S->n_x;
+
+ /* Coefficients (a==y for i<=n-1) */
+ float32_t * b = (S->coeffs);
+ float32_t * c = (S->coeffs)+(n-1);
+ float32_t * d = (S->coeffs)+(2*(n-1));
+
+ const float32_t * pXq = xq;
+ int32_t blkCnt = (int32_t)blockSize;
+ int32_t blkCnt2;
+ int32_t i;
+ float32_t x_sc;
+
+#ifdef ARM_MATH_NEON
+ float32x4_t xiv;
+ float32x4_t aiv;
+ float32x4_t biv;
+ float32x4_t civ;
+ float32x4_t div;
+
+ float32x4_t xqv;
+
+ float32x4_t temp;
+ float32x4_t diff;
+ float32x4_t yv;
+#endif
+
+ /* Create output for x(i)<x<x(i+1) */
+ for (i=0; i<n-1; i++)
+ {
+#ifdef ARM_MATH_NEON
+ xiv = vdupq_n_f32(x[i]);
+
+ aiv = vdupq_n_f32(y[i]);
+ biv = vdupq_n_f32(b[i]);
+ civ = vdupq_n_f32(c[i]);
+ div = vdupq_n_f32(d[i]);
+
+ while( *(pXq+4) <= x[i+1] && blkCnt > 4 )
+ {
+ /* Load [xq(k) xq(k+1) xq(k+2) xq(k+3)] */
+ xqv = vld1q_f32(pXq);
+ pXq+=4;
+
+ /* Compute [xq(k)-x(i) xq(k+1)-x(i) xq(k+2)-x(i) xq(k+3)-x(i)] */
+ diff = vsubq_f32(xqv, xiv);
+ temp = diff;
+
+ /* y(i) = a(i) + ... */
+ yv = aiv;
+ /* ... + b(i)*(x-x(i)) + ... */
+ yv = vmlaq_f32(yv, biv, temp);
+ /* ... + c(i)*(x-x(i))^2 + ... */
+ temp = vmulq_f32(temp, diff);
+ yv = vmlaq_f32(yv, civ, temp);
+ /* ... + d(i)*(x-x(i))^3 */
+ temp = vmulq_f32(temp, diff);
+ yv = vmlaq_f32(yv, div, temp);
+
+ /* Store [y(k) y(k+1) y(k+2) y(k+3)] */
+ vst1q_f32(pDst, yv);
+ pDst+=4;
+
+ blkCnt-=4;
+ }
+#endif
+ while( *pXq <= x[i+1] && blkCnt > 0 )
+ {
+ x_sc = *pXq++;
+
+ *pDst = y[i]+b[i]*(x_sc-x[i])+c[i]*(x_sc-x[i])*(x_sc-x[i])+d[i]*(x_sc-x[i])*(x_sc-x[i])*(x_sc-x[i]);
+
+ pDst++;
+ blkCnt--;
+ }
+ }
+
+ /* Create output for remaining samples (x>=x(n)) */
+#ifdef ARM_MATH_NEON
+ /* Compute 4 outputs at a time */
+ blkCnt2 = blkCnt >> 2;
+
+ while(blkCnt2 > 0)
+ {
+ /* Load [xq(k) xq(k+1) xq(k+2) xq(k+3)] */
+ xqv = vld1q_f32(pXq);
+ pXq+=4;
+
+ /* Compute [xq(k)-x(i) xq(k+1)-x(i) xq(k+2)-x(i) xq(k+3)-x(i)] */
+ diff = vsubq_f32(xqv, xiv);
+ temp = diff;
+
+ /* y(i) = a(i) + ... */
+ yv = aiv;
+ /* ... + b(i)*(x-x(i)) + ... */
+ yv = vmlaq_f32(yv, biv, temp);
+ /* ... + c(i)*(x-x(i))^2 + ... */
+ temp = vmulq_f32(temp, diff);
+ yv = vmlaq_f32(yv, civ, temp);
+ /* ... + d(i)*(x-x(i))^3 */
+ temp = vmulq_f32(temp, diff);
+ yv = vmlaq_f32(yv, div, temp);
+
+ /* Store [y(k) y(k+1) y(k+2) y(k+3)] */
+ vst1q_f32(pDst, yv);
+ pDst+=4;
+
+ blkCnt2--;
+ }
+
+ /* Tail */
+ blkCnt2 = blkCnt & 3;
+#else
+ blkCnt2 = blkCnt;
+#endif
+
+ while(blkCnt2 > 0)
+ {
+ x_sc = *pXq++;
+
+ *pDst = y[i-1]+b[i-1]*(x_sc-x[i-1])+c[i-1]*(x_sc-x[i-1])*(x_sc-x[i-1])+d[i-1]*(x_sc-x[i-1])*(x_sc-x[i-1])*(x_sc-x[i-1]);
+
+ pDst++;
+ blkCnt2--;
+ }
+}
+
+/**
+ @} end of SplineInterpolate group
+ */
diff --git a/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_init_f32.c b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_init_f32.c
new file mode 100644
index 0000000..ae3f2da
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/InterpolationFunctions/arm_spline_interp_init_f32.c
@@ -0,0 +1,175 @@
+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_spline_interp_init_f32.c
+ * Description: Floating-point cubic spline initialization function
+ *
+ * $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/interpolation_functions.h"
+
+/**
+ @ingroup groupInterpolation
+ */
+
+/**
+ @addtogroup SplineInterpolate
+ @{
+
+ @par Initialization function
+
+ The initialization function takes as input two arrays that the user has to allocate:
+ <code>coeffs</code> will contain the b, c, and d coefficients for the (n-1) intervals
+ (n is the number of known points), hence its size must be 3*(n-1); <code>tempBuffer</code>
+ is temporally used for internal computations and its size is n+n-1.
+
+ @par
+
+ The x input array must be strictly sorted in ascending order and it must
+ not contain twice the same value (x(i)<x(i+1)).
+
+*/
+
+/**
+ * @brief Initialization function for the floating-point cubic spline interpolation.
+ * @param[in,out] S points to an instance of the floating-point spline structure.
+ * @param[in] type type of cubic spline interpolation (boundary conditions)
+ * @param[in] x points to the x values of the known data points.
+ * @param[in] y points to the y values of the known data points.
+ * @param[in] n number of known data points.
+ * @param[in] coeffs coefficients array for b, c, and d
+ * @param[in] tempBuffer buffer array for internal computations
+ *
+ */
+
+void arm_spline_init_f32(
+ arm_spline_instance_f32 * S,
+ arm_spline_type type,
+ const float32_t * x,
+ const float32_t * y,
+ uint32_t n,
+ float32_t * coeffs,
+ float32_t * tempBuffer)
+{
+ /*** COEFFICIENTS COMPUTATION ***/
+ /* Type (boundary conditions):
+ - Natural spline ( S1''(x1) = 0 ; Sn''(xn) = 0 )
+ - Parabolic runout spline ( S1''(x1) = S2''(x2) ; Sn-1''(xn-1) = Sn''(xn) ) */
+
+ /* (n-1)-long buffers for b, c, and d coefficients */
+ float32_t * b = coeffs;
+ float32_t * c = coeffs+(n-1);
+ float32_t * d = coeffs+(2*(n-1));
+
+ float32_t * u = tempBuffer; /* (n-1)-long scratch buffer for u elements */
+ float32_t * z = tempBuffer+(n-1); /* n-long scratch buffer for z elements */
+
+ float32_t hi, hm1; /* h(i) and h(i-1) */
+ float32_t Bi; /* B(i), i-th element of matrix B=LZ */
+ float32_t li; /* l(i), i-th element of matrix L */
+ float32_t cp1; /* Temporary value for c(i+1) */
+
+ int32_t i; /* Loop counter */
+
+ S->x = x;
+ S->y = y;
+ S->n_x = n;
+
+ /* == Solve LZ=B to obtain z(i) and u(i) == */
+
+ /* -- Row 1 -- */
+ /* B(0) = 0, not computed */
+ /* u(1,2) = a(1,2)/a(1,1) = a(1,2) */
+ if(type == ARM_SPLINE_NATURAL)
+ u[0] = 0; /* a(1,2) = 0 */
+ else if(type == ARM_SPLINE_PARABOLIC_RUNOUT)
+ u[0] = -1; /* a(1,2) = -1 */
+
+ z[0] = 0; /* z(1) = B(1)/a(1,1) = 0 always */
+
+ /* -- Rows 2 to N-1 (N=n+1) -- */
+ hm1 = x[1] - x[0]; /* Initialize h(i-1) = h(1) = x(2)-x(1) */
+
+ for (i=1; i<(int32_t)n-1; i++)
+ {
+ /* Compute B(i) */
+ hi = x[i+1]-x[i];
+ Bi = 3*(y[i+1]-y[i])/hi - 3*(y[i]-y[i-1])/hm1;
+
+ /* l(i) = a(i)-a(i,i-1)*u(i-1) = 2[h(i-1)+h(i)]-h(i-1)*u(i-1) */
+ li = 2*(hi+hm1) - hm1*u[i-1];
+
+ /* u(i) = a(i,i+1)/l(i) = h(i)/l(i) */
+ u[i] = hi/li;
+
+ /* z(i) = [B(i)-h(i-1)*z(i-1)]/l(i) */
+ z[i] = (Bi-hm1*z[i-1])/li;
+
+ /* Update h(i-1) for next iteration */
+ hm1 = hi;
+ }
+
+ /* -- Row N -- */
+ /* l(N) = a(N,N)-a(N,N-1)u(N-1) */
+ /* z(N) = [-a(N,N-1)z(N-1)]/l(N) */
+ if(type == ARM_SPLINE_NATURAL)
+ {
+ /* li = 1; a(N,N) = 1; a(N,N-1) = 0 */
+ z[n-1] = 0; /* a(N,N-1) = 0 */
+ }
+ else if(type == ARM_SPLINE_PARABOLIC_RUNOUT)
+ {
+ li = 1+u[n-2]; /* a(N,N) = 1; a(N,N-1) = -1 */
+ z[n-1] = z[n-2]/li; /* a(N,N-1) = -1 */
+ }
+
+ /* == Solve UX = Z to obtain c(i) and */
+ /* compute b(i) and d(i) from c(i) == */
+
+ cp1 = z[n-1]; /* Initialize c(i+1) = c(N) = z(N) */
+
+ for (i=n-2; i>=0; i--)
+ {
+ /* c(i) = z(i)-u(i+1)c(i+1) */
+ c[i] = z[i]-u[i]*cp1;
+
+ hi = x[i+1]-x[i];
+ /* b(i) = [y(i+1)-y(i)]/h(i)-h(i)*[c(i+1)+2*c(i)]/3 */
+ b[i] = (y[i+1]-y[i])/hi-hi*(cp1+2*c[i])/3;
+
+ /* d(i) = [c(i+1)-c(i)]/[3*h(i)] */
+ d[i] = (cp1-c[i])/(3*hi);
+
+ /* Update c(i+1) for next iteration */
+ cp1 = c[i];
+ }
+
+ /* == Finally, store the coefficients in the instance == */
+
+ S->coeffs = coeffs;
+}
+
+/**
+ @} end of SplineInterpolate group
+ */
+