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tools:matrix:start [2021/11/12 11:44] – [Logging Matrices] ursgraftools:matrix:start [2022/04/20 13:29] (current) – [Logging Matrices] ursgraf
Line 3: Line 3:
 <code cpp> <code cpp>
 Vector<3, double> v;  Vector<3, double> v; 
-v << 1.5, -2, 0; 
 </code> </code>
 The declaration could be simplified to  The declaration could be simplified to 
 <code cpp> <code cpp>
 Vector3<> v;  Vector3<> v; 
-v << 1.5, -2, 0; 
 </code> </code>
-as ''Vector3'' is a predefined type with three dimensions and the default element type is ''double''. A matrix of 3 times 3 with element type ''int'' could be defined as+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} 
 +v << 1.5, -2, 0; // or with input operator 
 +Vector3 v{1,2,3}; // or directly upon declaration 
 +</code> 
 +A matrix of 3 times 3 with element type ''int'' could be defined as
 <code cpp> <code cpp>
 Matrix<3, 3, int> m;  Matrix<3, 3, int> m; 
-m << 1, 47+m << 1, 23
-     2, 5, 8+     4, 5, 6
-     36, 9;+     78, 9;
 </code> </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^ | ^col0^col1^col2^
Line 23: Line 27:
 ^row1|4|5|6| ^row1|4|5|6|
 ^row2|7|8|9| ^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 ===== ===== Accessing Elements =====
 You can access rows, columns or single elements of matrices with the following methods: You can access rows, columns or single elements of matrices with the following methods:
 <code cpp> <code cpp>
 m.get(0,0);  // returns element, 1 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> </code>
 Single elements, rows or columns can be written with the methods //set()//, //setRow()//, or //setCol()// Single elements, rows or columns can be written with the methods //set()//, //setRow()//, or //setCol()//
Line 61: Line 69:
 <code> <code>
 2021-09-16 17:37:18:122    I:  [1]' 2021-09-16 17:37:18:122    I:  [1]'
-2021-09-16 17:37:18:122    I:  [1 2]' +2021-09-16 17:37:18:122    I:  [1 2]'         // one colon with two rows 
-2021-09-16 17:37:18:122    I:  [ [1]' [2]' ]'+2021-09-16 17:37:18:122    I:  [ [1]' [2]' ]' // one row with two colons 
 +</code> 
 + 
 +===== 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> </code>
tools/matrix/start.1636713866.txt.gz · Last modified: 2021/11/12 11:44 by ursgraf