From f0238cfb6997c4acfc2bd200de7295f3fa36968f Mon Sep 17 00:00:00 2001 From: Stanislaw Halik Date: Sun, 3 Mar 2019 21:09:10 +0100 Subject: don't index Eigen --- eigen/doc/TutorialAdvancedInitialization.dox | 162 --------------------------- 1 file changed, 162 deletions(-) delete mode 100644 eigen/doc/TutorialAdvancedInitialization.dox (limited to 'eigen/doc/TutorialAdvancedInitialization.dox') diff --git a/eigen/doc/TutorialAdvancedInitialization.dox b/eigen/doc/TutorialAdvancedInitialization.dox deleted file mode 100644 index 50374d0..0000000 --- a/eigen/doc/TutorialAdvancedInitialization.dox +++ /dev/null @@ -1,162 +0,0 @@ -namespace Eigen { - -/** \eigenManualPage TutorialAdvancedInitialization Advanced initialization - -This page discusses several advanced methods for initializing matrices. It gives more details on the -comma-initializer, which was introduced before. It also explains how to get special matrices such as the -identity matrix and the zero matrix. - -\eigenAutoToc - -\section TutorialAdvancedInitializationCommaInitializer The comma initializer - -Eigen offers a comma initializer syntax which allows the user to easily set all the coefficients of a matrix, -vector or array. Simply list the coefficients, starting at the top-left corner and moving from left to right -and from the top to the bottom. The size of the object needs to be specified beforehand. If you list too few -or too many coefficients, Eigen will complain. - - - - -
Example:Output:
-\include Tutorial_commainit_01.cpp - -\verbinclude Tutorial_commainit_01.out -
- -Moreover, the elements of the initialization list may themselves be vectors or matrices. A common use is -to join vectors or matrices together. For example, here is how to join two row vectors together. Remember -that you have to set the size before you can use the comma initializer. - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_Join.cpp - -\verbinclude Tutorial_AdvancedInitialization_Join.out -
- -We can use the same technique to initialize matrices with a block structure. - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_Block.cpp - -\verbinclude Tutorial_AdvancedInitialization_Block.out -
- -The comma initializer can also be used to fill block expressions such as m.row(i). Here is a more -complicated way to get the same result as in the first example above: - - - - -
Example:Output:
-\include Tutorial_commainit_01b.cpp - -\verbinclude Tutorial_commainit_01b.out -
- - -\section TutorialAdvancedInitializationSpecialMatrices Special matrices and arrays - -The Matrix and Array classes have static methods like \link DenseBase::Zero() Zero()\endlink, which can be -used to initialize all coefficients to zero. There are three variants. The first variant takes no arguments -and can only be used for fixed-size objects. If you want to initialize a dynamic-size object to zero, you need -to specify the size. Thus, the second variant requires one argument and can be used for one-dimensional -dynamic-size objects, while the third variant requires two arguments and can be used for two-dimensional -objects. All three variants are illustrated in the following example: - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_Zero.cpp - -\verbinclude Tutorial_AdvancedInitialization_Zero.out -
- -Similarly, the static method \link DenseBase::Constant() Constant\endlink(value) sets all coefficients to \c value. -If the size of the object needs to be specified, the additional arguments go before the \c value -argument, as in MatrixXd::Constant(rows, cols, value). The method \link DenseBase::Random() Random() -\endlink fills the matrix or array with random coefficients. The identity matrix can be obtained by calling -\link MatrixBase::Identity() Identity()\endlink; this method is only available for Matrix, not for Array, -because "identity matrix" is a linear algebra concept. The method -\link DenseBase::LinSpaced LinSpaced\endlink(size, low, high) is only available for vectors and -one-dimensional arrays; it yields a vector of the specified size whose coefficients are equally spaced between -\c low and \c high. The method \c LinSpaced() is illustrated in the following example, which prints a table -with angles in degrees, the corresponding angle in radians, and their sine and cosine. - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_LinSpaced.cpp - -\verbinclude Tutorial_AdvancedInitialization_LinSpaced.out -
- -This example shows that objects like the ones returned by LinSpaced() can be assigned to variables (and -expressions). Eigen defines utility functions like \link DenseBase::setZero() setZero()\endlink, -\link MatrixBase::setIdentity() \endlink and \link DenseBase::setLinSpaced() \endlink to do this -conveniently. The following example contrasts three ways to construct the matrix -\f$ J = \bigl[ \begin{smallmatrix} O & I \\ I & O \end{smallmatrix} \bigr] \f$: using static methods and -assignment, using static methods and the comma-initializer, or using the setXxx() methods. - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_ThreeWays.cpp - -\verbinclude Tutorial_AdvancedInitialization_ThreeWays.out -
- -A summary of all pre-defined matrix, vector and array objects can be found in the \ref QuickRefPage. - - -\section TutorialAdvancedInitializationTemporaryObjects Usage as temporary objects - -As shown above, static methods as Zero() and Constant() can be used to initialize variables at the time of -declaration or at the right-hand side of an assignment operator. You can think of these methods as returning a -matrix or array; in fact, they return so-called \ref TopicEigenExpressionTemplates "expression objects" which -evaluate to a matrix or array when needed, so that this syntax does not incur any overhead. - -These expressions can also be used as a temporary object. The second example in -the \ref GettingStarted guide, which we reproduce here, already illustrates this. - - - - -
Example:Output:
-\include QuickStart_example2_dynamic.cpp - -\verbinclude QuickStart_example2_dynamic.out -
- -The expression m + MatrixXf::Constant(3,3,1.2) constructs the 3-by-3 matrix expression with all its coefficients -equal to 1.2 plus the corresponding coefficient of \a m. - -The comma-initializer, too, can also be used to construct temporary objects. The following example constructs a random -matrix of size 2-by-3, and then multiplies this matrix on the left with -\f$ \bigl[ \begin{smallmatrix} 0 & 1 \\ 1 & 0 \end{smallmatrix} \bigr] \f$. - - - - -
Example:Output:
-\include Tutorial_AdvancedInitialization_CommaTemporary.cpp - -\verbinclude Tutorial_AdvancedInitialization_CommaTemporary.out -
- -The \link CommaInitializer::finished() finished() \endlink method is necessary here to get the actual matrix -object once the comma initialization of our temporary submatrix is done. - - -*/ - -} -- cgit v1.2.3