Laxmi Kant Tiwari
CMSIS DSP Lib
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Diff: cmsis_dsp/MatrixFunctions/arm_mat_inverse_f32.c
- Revision:
- 3:7a284390b0ce
- Parent:
- 2:da51fb522205
--- a/cmsis_dsp/MatrixFunctions/arm_mat_inverse_f32.c Thu May 30 17:10:11 2013 +0100
+++ b/cmsis_dsp/MatrixFunctions/arm_mat_inverse_f32.c Fri Nov 08 13:45:10 2013 +0000
@@ -1,8 +1,8 @@
/* ----------------------------------------------------------------------
-* Copyright (C) 2010 ARM Limited. All rights reserved.
+* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
*
-* $Date: 15. February 2012
-* $Revision: V1.1.0
+* $Date: 1. March 2013
+* $Revision: V1.4.1
*
* Project: CMSIS DSP Library
* Title: arm_mat_inverse_f32.c
@@ -11,23 +11,31 @@
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
-* Version 1.1.0 2012/02/15
-* Updated with more optimizations, bug fixes and minor API changes.
-*
-* Version 1.0.10 2011/7/15
-* Big Endian support added and Merged M0 and M3/M4 Source code.
-*
-* Version 1.0.3 2010/11/29
-* Re-organized the CMSIS folders and updated documentation.
-*
-* Version 1.0.2 2010/11/11
-* Documentation updated.
-*
-* Version 1.0.1 2010/10/05
-* Production release and review comments incorporated.
-*
-* Version 1.0.0 2010/09/20
-* Production release and review comments incorporated.
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* - Redistributions of source code must retain the above copyright
+* notice, this list of conditions and the following disclaimer.
+* - Redistributions in binary form must reproduce the above copyright
+* notice, this list of conditions and the following disclaimer in
+* the documentation and/or other materials provided with the
+* distribution.
+* - Neither the name of ARM LIMITED nor the names of its contributors
+* may be used to endorse or promote products derived from this
+* software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+* POSSIBILITY OF SUCH DAMAGE.
* -------------------------------------------------------------------- */
#include "arm_math.h"
@@ -86,7 +94,8 @@
uint32_t numRows = pSrc->numRows; /* Number of rows in the matrix */
uint32_t numCols = pSrc->numCols; /* Number of Cols in the matrix */
-#ifndef ARM_MATH_CM0
+#ifndef ARM_MATH_CM0_FAMILY
+ float32_t maxC; /* maximum value in the column */
/* Run the below code for Cortex-M4 and Cortex-M3 */
@@ -125,12 +134,13 @@
*
* 3. Begin with the first row. Let i = 1.
*
- * 4. Check to see if the pivot for row i is zero.
+ * 4. Check to see if the pivot for column i is the greatest of the column.
* The pivot is the element of the main diagonal that is on the current row.
* For instance, if working with row i, then the pivot element is aii.
- * If the pivot is zero, exchange that row with a row below it that does not
- * contain a zero in column i. If this is not possible, then an inverse
- * to that matrix does not exist.
+ * If the pivot is not the most significant of the coluimns, exchange that row with a row
+ * below it that does contain the most significant value in column i. If the most
+ * significant value of the column is zero, then an inverse to that matrix does not exist.
+ * The most significant value of the column is the absolut maximum.
*
* 5. Divide every element of row i by the pivot.
*
@@ -204,8 +214,26 @@
/* Destination pointer modifier */
k = 1u;
- /* Check if the pivot element is zero */
- if(*pInT1 == 0.0f)
+ /* Grab the most significant value from column l */
+ maxC = 0;
+ for (i = 0; i < numRows; i++)
+ {
+ maxC = *pInT1 > 0 ? (*pInT1 > maxC ? *pInT1 : maxC) : (-*pInT1 > maxC ? -*pInT1 : maxC);
+ pInT1 += numCols;
+ }
+
+ /* Update the status if the matrix is singular */
+ if(maxC == 0.0f)
+ {
+ status = ARM_MATH_SINGULAR;
+ break;
+ }
+
+ /* Restore pInT1 */
+ pInT1 -= numRows * numCols;
+
+ /* Check if the pivot element is the most significant of the column */
+ if( (in > 0.0f ? in : -in) != maxC)
{
/* Loop over the number rows present below */
i = numRows - (l + 1u);
@@ -216,9 +244,9 @@
pInT2 = pInT1 + (numCols * l);
pInT4 = pInT3 + (numCols * k);
- /* Check if there is a non zero pivot element to
+ /* Look for the most significant element to
* replace in the rows below */
- if(*pInT2 != 0.0f)
+ if((*pInT2 > 0.0f ? *pInT2: -*pInT2) == maxC)
{
/* Loop over number of columns
* to the right of the pilot element */
@@ -281,7 +309,7 @@
pInT2 = pPivotRowDst;
/* Pivot element of the row */
- in = *(pIn + (l * numCols));
+ in = *pPivotRowIn;
/* Loop over number of columns
* to the right of the pilot element */
@@ -583,13 +611,15 @@
{
/* Divide each element of the row of the input matrix
* by the pivot element */
- *pInT1++ = *pInT1 / in;
+ *pInT1 = *pInT1 / in;
+ pInT1++;
}
for (j = 0u; j < numCols; j++)
{
/* Divide each element of the row of the destination matrix
* by the pivot element */
- *pInT2++ = *pInT2 / in;
+ *pInT2 = *pInT2 / in;
+ pInT2++;
}
/* Replace the rows with the sum of that row and a multiple of row i
@@ -624,7 +654,8 @@
{
/* Replace the element by the sum of that row
and a multiple of the reference row */
- *pInT1++ = *pInT1 - (in * *pPRT_in++);
+ *pInT1 = *pInT1 - (in * *pPRT_in++);
+ pInT1++;
}
/* Loop over the number of columns to
replace the elements in the destination matrix */
@@ -632,7 +663,8 @@
{
/* Replace the element by the sum of that row
and a multiple of the reference row */
- *pInT2++ = *pInT2 - (in * *pPRT_pDst++);
+ *pInT2 = *pInT2 - (in * *pPRT_pDst++);
+ pInT2++;
}
}
@@ -649,7 +681,7 @@
}
-#endif /* #ifndef ARM_MATH_CM0 */
+#endif /* #ifndef ARM_MATH_CM0_FAMILY */
/* Set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;