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Diffstat (limited to 'src/electronics/simulation/matrix.h')
| -rw-r--r-- | src/electronics/simulation/matrix.h | 248 |
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diff --git a/src/electronics/simulation/matrix.h b/src/electronics/simulation/matrix.h new file mode 100644 index 0000000..4c3e518 --- /dev/null +++ b/src/electronics/simulation/matrix.h @@ -0,0 +1,248 @@ +/*************************************************************************** + * Copyright (C) 2003-2004 by David Saxton * + * david@bluehaze.org * + * * + * This program is free software; you can redistribute it and/or modify * + * it under the terms of the GNU General Public License as published by * + * the Free Software Foundation; either version 2 of the License, or * + * (at your option) any later version. * + ***************************************************************************/ + +#ifndef MATRIX_H +#define MATRIX_H + +#include "vec.h" + +#include <vector> + +class Map; + +typedef std::vector<std::vector<uint> > ETMap; + +/** +@short Handles row-wise permutation of matrixes +*/ +class Map +{ +public: + enum e_type + { + et_none = 0x0, // Default value, none + et_constant = 0x1, // Never changes value in lifetime of matrix + et_stable = 0x2, // Value changes occasionally, e.g. user changing resistance value + et_variable = 0x3, // Rate of changing is unknown, probably average - e.g. logic + et_unstable = 0x4, // Value changes practically every call of performLU + et_big = 0x8 // Ignore this :-) It is used to OR with one of the others, but it should only ever be accessed by the class + }; + Map( const uint size ); + ~Map(); + + void setUse( const uint i, const uint j, Map::e_type type, bool big ); + /** + * Generates an optimal permutation, returned in the given array + */ + void createMap( int *map ); + /** + * Resets the info to a blank pattern + */ + void reset(); + +protected: + /** + * Compares two "types", returning true if t1 >= t2, else false + */ + bool typeCmp( const uint t1, const uint t2 ); + +private: + ETMap *m_map; + uint m_size; +}; + +/** +This class performs matrix storage, lu decomposition, forward and backward +substitution, and a few other useful operations. Steps in using class: +(1) Create an instance of this class with the correct size +(2) Define the matrix pattern as neccessary: + (1) Call zero (unnecessary after initial ceration) to reset the pattern + & matrix + (2) Call setUse to set the use of each element in the matrix + (3) Call createMap to generate the row-wise permutation mapping for use + in partial pivoting +(3) Add the values to the matrix +(4) Call performLU, and get the results with fbSub +(5) Repeat 2, 3, 4 or 5 as necessary. +@todo We need to allow createMap to work while the matrix has already been initalised +@short Matrix manipulation class tailored for circuit equations +@author David Saxton +*/ +class Matrix +{ +public: + /** + * Creates a size x size square matrix m, with all values zero, + * and a right side vector x of size m+n + */ + Matrix( uint n, uint m ); + ~Matrix(); + /** + * Sets all elements to zero + */ + void zero(); + /** + * Sets the type of (matrix-) element at the position i, j. + * @param type Describes how often the value changes + * @param big Set this true if the value is likely to be >= 1, else false + */ + void setUse( const uint i, const uint j, Map::e_type type, bool big ); + void setUse_b( const uint i, const uint j, Map::e_type type, bool big ) + { + setUse( i, j+m_n, type, big ); + } + void setUse_c( const uint i, const uint j, Map::e_type type, bool big ) + { + setUse( i+m_n, j, type, big ); + } + void setUse_d( const uint i, const uint j, Map::e_type type, bool big ) + { + setUse( i+m_n, j+m_n, type, big ); + } + /** + * Generates the row-wise permutation mapping from the values set by setUse + */ + void createMap(); + /** + * Returns true if the matrix is changed since last calling performLU() + * - i.e. if we do need to call performLU again. + */ + inline bool isChanged() const { return max_k < m_size; } + /** + * Performs LU decomposition. Going along the rows, + * the value of the decomposed LU matrix depends only on + * the previous values. + */ + void performLU(); + /** + * Applies the right side vector (x) to the decomposed matrix, + * with the solution returned in x. + */ + void fbSub( Vector* x ); + /** + * Prints the matrix to stdout + */ + void displayMatrix(); + /** + * Prints the LU-decomposed matrix to stdout + */ + void displayLU(); + /** + * Sets the element matrix at row i, col j to value x + */ + double& g( uint i, uint j ) + { + i = m_inMap[i]; + if ( i<max_k ) max_k=i; + if ( j<max_k ) max_k=j; + + // I think I need the next line... + if ( max_k>0 ) max_k--; + + return (*m_mat)[i][j]; + } + double& b( uint i, uint j ) { return g( i, j+m_n ); } + double& c( uint i, uint j ) { return g( i+m_n, j ); } + double& d( uint i, uint j ) { return g( i+m_n, j+m_n ); } + const double g( uint i, uint j ) const { return (*m_mat)[m_inMap[i]][j]; } + const double b( uint i, uint j ) const { return g( i, j+m_n ); } + const double c( uint i, uint j ) const { return g( i+m_n, j ); } + const double d( uint i, uint j ) const { return g( i+m_n, j+m_n ); } + /** + * Returns the value of matrix at row i, col j. + */ + const double m( uint i, uint j ) const + { + return (*m_mat)[m_inMap[i]][j]; + } + /** + * Multiplies this matrix by the Vector rhs, and places the result + * in the vector pointed to by result. Will fail if wrong size. + */ + void multiply( Vector *rhs, Vector *result ); + /** + * Sets the values of this matrix to that of the given matrix + */ + void operator=( Matrix *const m ); + /** + * Adds the values of the given matrix to this matrix + */ + void operator+=( Matrix *const m ); + +private: + /** + * Swaps around the rows in the (a) the matrix; and (b) the mappings + */ + void swapRows( const uint a, const uint b ); + +// // Generates m_outMap from m_inMap +// void genOutMap(); + + uint m_n; + uint m_m; + uint m_size; + uint max_k; + + int *m_inMap; // Rowwise permutation mapping from external reference to internal storage +// int *m_outMap; // Opposite of m_inMap + + matrix *m_mat; + matrix *m_lu; + double *m_y; // Avoids recreating it lots of times + Map *m_map; +}; + + +/** +This class provides a very simple, lightweight, 2x2 matrix solver. +It's fast and reliable. Set the values for the entries of A and b: + +A x = b + +call solve() (which returns true if successful - i.e. exactly one solution to the +matrix), and get the values of x with the appropriate functions. + +@short 2x2 Matrix +@author David Saxton +*/ +class Matrix22 +{ +public: + Matrix22(); + + double &a11() { return m_a11; } + double &a12() { return m_a12; } + double &a21() { return m_a21; } + double &a22() { return m_a22; } + + double &b1() { return m_b1; } + double &b2() { return m_b2; } + + /** + * Solve the matrix. Returns true if successful (i.e. non-singular), else + * false. Get the solution with x1() and x2(). + */ + bool solve(); + /** + * Resets all entries to zero + */ + void reset(); + + double x1() const { return m_x1; } + double x2() const { return m_x2; } + +private: + double m_a11, m_a12, m_a21, m_a22; + double m_b1, m_b2; + double m_x1, m_x2; +}; + + +#endif |