* update redux section

* fix output precision to 3 for the snippets

doc/C01_TutorialCore.dox

@@ -3,6 +3,8 @@ namespace Eigen {
 /** \page TutorialCore Tutorial 1/4 - Core features
     \ingroup Tutorial
 
+<p style="font-size:2em"> WARNING this page is deprecated, and will be removed soon, don't look at it :) </p>
+
 <div class="eimainmenu">\ref index "Overview"
   | \b Core \b features
   | \ref TutorialGeometry "Geometry"

doc/C02_TutorialMatrixArithmetic.dox

@@ -143,53 +143,28 @@ When using complex numbers, Eigen's dot product is conjugate-linear in the first
 second variable.
 
 \section TutorialArithmeticRedux Basic arithmetic reduction operations
-Eigen also provides some reduction operations to obtain values such as the sum or the maximum
+Eigen also provides some reduction operations to reduce a given matrix or vector to a single value such as the sum (<tt>a.sum()</tt>), product (<tt>a.sum()</tt>), or the maximum (<tt>a.maxCoeff()</tt>) and minimum (<tt>a.minCoeff()</tt>) of all its coefficients.
-or minimum of all the coefficients in a given matrix or vector.
 
-TODO: convert this from table format to tutorial/examples format.
+<table class="tutorial_code"><tr><td>
+Example: \include tut_arithmetic_redux_basic.cpp
+</td>
+<td>
+Output: \include tut_arithmetic_redux_basic.out
+</td></tr></table>
 
-<table class="tutorial_code" align="center">
+The \em trace of a matrix, as returned by the function \c trace(), is the sum of the diagonal coefficients and can also be computed as efficiently using <tt>a.diagonal().sum()</tt>, as we see later on.
-<tr><td align="center">\b Reduction \b operation</td><td align="center">\b Usage \b example</td></tr>
-<tr><td>
-Sum of all the coefficients in a matrix</td><td>\code
-MatrixXf m;
-float totalSum = m.sum();\endcode</td></tr>
-<tr><td>
-Maximum coefficient in a matrix</td><td>\code
-MatrixXf m;
-int row, col;
 
-// minimum value will be stored in minValue
+There also exist variants of the \c minCoeff and \c maxCoeff functions returning the coordinates of the respective coefficient via the arguments:
-//  and the row and column where it was found in row and col,
-//  (these two parameters are optional)
-float minValue = m.minCoeff(&row,&col);\endcode</td></tr>
-<tr><td>
-Maximum coefficient in a matrix</td><td>\code
-MatrixXf m;
-int row, col;
 
-// maximum value will be stored in maxValue
+<table class="tutorial_code"><tr><td>
-//  and the row and column where it was found in row and col,
+Example: \include tut_arithmetic_redux_minmax.cpp
-//  (these two parameters are optional)
+</td>
-float maxValue = m.maxCoeff(&row,&col);\endcode</td></tr>
+<td>
-<tr><td>
+Output: \include tut_arithmetic_redux_minmax.out
-Product between all coefficients in a matrix</td><td>\code
+</td></tr></table>
-MatrixXf m;
 
-float product = m.prod();\endcode</td></tr>
-<tr><td>
-Mean of coefficients in a matrix</td><td>\code
-MatrixXf m;
 
-float mean = m.mean();\endcode</td></tr>
+\section TutorialArithmeticValidity Validity of operations
-<tr><td>
-Matrix's trace</td><td>\code
-MatrixXf m;
-
-float trace = m.trace();\endcode</td></tr>
-</table>
-
-\subsection TutorialArithmeticValidity Validity of operations
 Eigen checks the validity of the operations that you perform. When possible,
 it checks them at compile-time, producing compilation errors. These error messages can be long and ugly,
 but Eigen writes the important message in UPPERCASE_LETTERS_SO_IT_STANDS_OUT. For example:

doc/QuickReference.dox

@@ -35,6 +35,7 @@ namespace Eigen {
 <a href="#" class="top">top</a>
 \section QuickRef_Types Array, matrix and vector types
 
+
 \b Recall: Eigen provides two kinds of dense objects: mathematical matrices and vectors which are both represented by the template class Matrix, and general 1D and 2D arrays represented by the template class Array:
 \code
 typedef Matrix<Scalar, RowsAtCompileTime, ColsAtCompileTime, Options> MyMatrixType;
@@ -87,7 +88,6 @@ In the rest of this document we will use the following symbols to emphasize the
 \li <a name="matrixonly"><a/>\matrixworld linear algebra matrix and vector only
 \li <a name="arrayonly"><a/>\arrayworld array objects only
 
-
 \subsection QuickRef_Basics Basic matrix manipulation
 
 <table class="tutorial_code">

doc/examples/tut_arithmetic_redux_basic.cpp

@@ -0,0 +1,16 @@
+#include <iostream>
+#include <Eigen/Dense>
+
+using namespace std;
+int main()
+{
+  Eigen::Matrix2d mat;
+  mat << 1, 2,
+         3, 4;
+  cout << "Here is mat.sum():       " << mat.sum()       << endl;
+  cout << "Here is mat.prod():      " << mat.prod()      << endl;
+  cout << "Here is mat.mean():      " << mat.mean()      << endl;
+  cout << "Here is mat.minCoeff():  " << mat.minCoeff()  << endl;
+  cout << "Here is mat.maxCoeff():  " << mat.maxCoeff()  << endl;
+  cout << "Here is mat.trace():     " << mat.trace()     << endl;
+}

doc/snippets/compile_snippet.cpp.in

@@ -11,6 +11,7 @@ using namespace std;
 
 int main(int, char**)
 {
+  cout.precision(3);
   ${snippet_source_code}
   return 0;
 }

doc/snippets/tut_arithmetic_redux_minmax.cpp

@@ -0,0 +1,10 @@
+  Matrix3f m = Matrix3f::Random();
+  std::ptrdiff_t i, j;
+  float minOfM = m.minCoeff(&i,&j);
+  cout << "Here is the matrix m:\n" << m << endl;
+  cout << "Its minimum coefficient (" << minOfM << ") is at position (" << i << "," << j << ")\n\n";
+
+  RowVector4i v = RowVector4i::Random();
+  int maxOfV = v.maxCoeff(&i);
+  cout << "Here is the vector v: " << v << endl;
+  cout << "Its maximum coefficient (" << maxOfV << ") is at position " << i << endl;

doc/snippets/tut_arithmetic_transpose_aliasing.cpp

@@ -1,4 +1,5 @@
 Matrix2i a; a << 1, 2, 3, 4;
 cout << "Here is the matrix a:\n" << a << endl;
-a = a.transpose(); // fails
+
-cout << "and the aliasing effect:\n" << a << endl;
+a = a.transpose(); // !!! do NOT do this !!!
+cout << "and the result of the aliasing effect:\n" << a << endl;

doc/snippets/tut_arithmetic_transpose_inplace.cpp

@@ -1,4 +1,6 @@
 MatrixXf a(2,3); a << 1, 2, 3, 4, 5, 6;
 cout << "Here is the initial matrix a:\n" << a << endl;
+
+
 a.transposeInPlace();
 cout << "and after being transposed:\n" << a << endl;