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-              rcca9ef
+              r0d4424
 #include <gsl/gsl_blas.h>
 #include <gsl/gsl_eigen.h>
+#include <gsl/gsl_linalg.h>
 #include <gsl/gsl_matrix.h>
 #include <gsl/gsl_multimin.h>
 …
     for(int j=columns;j--;){
       set(i,j,0.);
+    }
+  }
+}
+/** Set all matrix components to a given value.
+ * \param _value value to set each component to
+ */
+void MatrixContent::setValue(double _value)
+{
+  for(int i=rows;i--;){
+    for(int j=columns;j--;){
+      set(i,j,_value);
+    }
+  }
 …
+}
+/* ========================== Accessing =============================== */
 /** Accessor for manipulating component (i,j).
  * \param i row number
 …
+}
+/** These functions return a pointer to the \a m-th element of a matrix.
+ *  If \a m or \a n lies outside the allowed range of 0 to GSLMatrix::dimension-1 then the error handler is invoked and a null pointer is returned.
+ * \param m index
+ * \return pointer to \a m-th element
+ */
+double *MatrixContent::Pointer(size_t m, size_t n)
+{
+  return gsl_matrix_ptr (content, m, n);
+};
+/** These functions return a constant pointer to the \a m-th element of a matrix.
+ *  If \a m or \a n lies outside the allowed range of 0 to GSLMatrix::dimension-1 then the error handler is invoked and a null pointer is returned.
+ * \param m index
+ * \return const pointer to \a m-th element
+ */
+const double *MatrixContent::const_Pointer(size_t m, size_t n) const
+{
+  return gsl_matrix_const_ptr (content, m, n);
+};
+/* ========================== Initializing =============================== */
 /** Setter for component (i,j).
  * \param i row numbr
 …
+}
+/** This function sets the matrix from a double array.
+ * Creates a matrix view of the array and performs a memcopy.
+ * \param *x array of values (no dimension check is performed)
+ */
+void MatrixContent::setFromDoubleArray(double * x)
+{
+  gsl_matrix_view m = gsl_matrix_view_array (x, rows, columns);
+  gsl_matrix_memcpy (content, &m.matrix);
+};
+/* ====================== Exchanging elements ============================ */
+/** This function exchanges the \a i-th and \a j-th row of the matrix in-place.
+ * \param i i-th row to swap with ...
+ * \param j ... j-th row to swap against
+ */
+bool MatrixContent::SwapRows(size_t i, size_t j)
+{
+  return (gsl_matrix_swap_rows (content, i, j) == GSL_SUCCESS);
+};
+/** This function exchanges the \a i-th and \a j-th column of the matrix in-place.
+ * \param i i-th column to swap with ...
+ * \param j ... j-th column to swap against
+ */
+bool MatrixContent::SwapColumns(size_t i, size_t j)
+{
+  return (gsl_matrix_swap_columns (content, i, j) == GSL_SUCCESS);
+};
+/** This function exchanges the \a i-th row and \a j-th column of the matrix in-place.
+ * The matrix must be square for this operation to be possible.
+ * \param i i-th row to swap with ...
+ * \param j ... j-th column to swap against
+ */
+bool MatrixContent::SwapRowColumn(size_t i, size_t j)
+{
+  assert (rows == columns && "The matrix must be square for swapping row against column to be possible.");
+  return (gsl_matrix_swap_rowcol (content, i, j) == GSL_SUCCESS);
+};
 /** Return transposed matrix.
  * \return new matrix that is transposed of this.
 …
+{
   std::cout << "const MatrixContent::transpose()." << std::endl;
   gsl_matrix *res = gsl_matrix_alloc(rows, columns);
+  gsl_matrix *res = gsl_matrix_alloc(columns, rows);  // column and row dimensions exchanged!
   gsl_matrix_transpose_memcpy(res, content);
   MatrixContent newContent(res);
 …
   return eval;
+}
+/* ============================ Properties ============================== */
+/** Checks whether matrix' elements are strictly null.
+ * \return true - is null, false - else
+ */
+bool MatrixContent::IsNull() const
+{
+  return gsl_matrix_isnull (content);
+};
+/** Checks whether matrix' elements are strictly positive.
+ * \return true - is positive, false - else
+ */
+bool MatrixContent::IsPositive() const
+{
+  return gsl_matrix_ispos (content);
+};
+/** Checks whether matrix' elements are strictly negative.
+ * \return true - is negative, false - else
+ */
+bool MatrixContent::IsNegative() const
+{
+  return gsl_matrix_isneg (content);
+};
+/** Checks whether matrix' elements are strictly non-negative.
+ * \return true - is non-negative, false - else
+ */
+bool MatrixContent::IsNonNegative() const
+{
+  return gsl_matrix_isnonneg (content);
+};
+/** This function performs a Cholesky decomposition to determine whether matrix is positive definite.
+ * We check whether GSL returns GSL_EDOM as error, indicating that decomposition failed due to matrix not being positive-definite.
+ * \return true - matrix is positive-definite, false - else
+ */
+bool MatrixContent::IsPositiveDefinite() const
+{
+  if (rows != columns)  // only possible for square matrices.
+    return false;
+  else
+    return (gsl_linalg_cholesky_decomp (content) != GSL_EDOM);
+};
+/** Calculates the determinant of the matrix.
+ * if matrix is square, uses LU decomposition.
+ */
+double MatrixContent::Determinant() const
+{
+  int signum = 0;
+  assert (rows == columns && "Determinant can only be calculated for square matrices.");
+  gsl_permutation *p = gsl_permutation_alloc(rows);
+  gsl_linalg_LU_decomp(content, p, &signum);
+  gsl_permutation_free(p);
+  return gsl_linalg_LU_det(content, signum);
+};
+/* ============================= Operators =============================== */
 /** Scalar multiplication operator.

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Changeset 0d4424 for src/LinearAlgebra/MatrixContent.cpp

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src/LinearAlgebra/MatrixContent.cpp

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