Differences

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--- tools:matrix:start [2021/11/14 16:41] – ursgraf
+++ tools:matrix:start [2022/04/20 12:45] – [Vectors and Matrices] ursgraf
@@ Line 8: / Line 8: @@
 Vector3<> v;
 </code>
-as ''Vector3'' is a predefined type with three dimensions and the default element type is ''double''. A ''Vector3'' is identical to the type ''Matrix<3,1,double>''. The vector could be initializer as follows
+as ''Vector3'' is a predefined type with three dimensions and the default element type is ''double''. A ''Vector3'' is identical to the type ''Matrix<3,1,double>''. The vector could be initialized as follows
 <code cpp>
 v = {1.5, -2, 0}
@@ Line 17: / Line 17: @@
 <code cpp>
 Matrix<3, 3, int> m;
-m << 1, 4, 7,
+m << 1, 2, 3,
-, 5, 8,
+, 5, 6,
-, 6, 9;
+, 8, 9;
 </code>
-The first three numbers will be filled into the first colon. While the internal representation is simply a one dimensional vector, the matrix could be visualized as
+The first three numbers will be filled into the first row. While the internal representation is simply a one dimensional vector, the matrix could be visualized as
 | ^col0^col1^col2^
@@ Line 27: / Line 27: @@
 ^row1|4|5|6|
 ^row2|7|8|9|
+When declaring and initializing a matrix, the values must be given colon per colon. The same matrix as given above would be initialized as follows
+<code cpp>
+Matrix<3, 3, int> m{1, 4, 7, 2, 5, 8, 3, 6, 9};
+</code>
 ===== Accessing Elements =====
 You can access rows, columns or single elements of matrices with the following methods:
 <code cpp>
 m.get(0,0);  // returns element, 1
-m.getRow(1);  // returns row, [2,5,8]
+m.get(1,0);  // returns element, 4
-m.getCol(0);  // returns column, [1,2,3]'
+m.getRow(1);  // returns row, [4,5,6]
-m.getSubMatrix<2,2>(0,1);   // returns matrix [[4,5][7,8]]
+m.getCol(0);  // returns column, [1,4,7]'
+m.getSubMatrix<2,2>(0,1);   // returns matrix [[2,5][3,6]]
 </code>
 Single elements, rows or columns can be written with the methods //set()//, //setRow()//, or //setCol()//.
@@ Line 70: / Line 74: @@
 ===== Matrix Operations =====
+Some examples show basic matrix operations.
+<code cpp>
+Vector2 v1{1,2};
+Matrix<1,2> v2{3,4};
+log.info() << v1 * v2;            // will print [ [3 6]' [4 8]' ]
+log.info() << v2 * v1;            // will print [11]'
+Matrix<2,2,double> m1{1,1.5,-1,2};
+log.info() << v2 * m1;            // will print [ [9]' [5]' ]
+log.info() << v1.transpose() * m1;// will print [ [4]' [3]' ]
+auto x = v2 * m1;
+Vector2 v4 = x.transpose();
+log.info() << v4;                 // will print [9 5]'
+</code>