numerik1/Projekt1_Knuettel_Daniel.c

128 lines
4.0 KiB
C

// Daniel Knüttel Aufgabe2
/*
* Copyright(c) 2018 Daniel Knüttel
*/
/* 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 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Dieses Programm ist Freie Software: Sie können es unter den Bedingungen
* der GNU General Public License, wie von der Free Software Foundation,
* Version 3 der Lizenz oder (nach Ihrer Wahl) jeder neueren
* veröffentlichten Version, weiterverbreiten und/oder modifizieren.
*
* Dieses Programm wird in der Hoffnung, dass es nützlich sein wird, aber
* OHNE JEDE GEWÄHRLEISTUNG, bereitgestellt; sogar ohne die implizite
* Gewährleistung der MARKTFÄHIGKEIT oder EIGNUNG FÜR EINEN BESTIMMTEN ZWECK.
* Siehe die GNU General Public License für weitere Details.
*
* Sie sollten eine Kopie der GNU General Public License zusammen mit diesem
* Programm erhalten haben. Wenn nicht, siehe <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
/*
* \brief Computes the householder partition of A.
* Stores the generating vectors of Q in the memory passed as A,
* the diagonal elements in alpha and the rest of R in the memory
* passed as A.
*
* \param A Matrix to partition. After the partition this memory contains Q and R.
* \param alpha Will be filled with diagonal elements of R.
* \param n Length of A[i].
* \param m Length of A.
* \return Status.
* */
int householder(double ** A, double * alpha, int n, int m);
/*
* \brief Computes the solution of and n times n system using a QR partition.
* Overwrites b.
*
* \param A Matrix that has been modified by the function householder.
* \param alpha Diagonal elements of R, produced by the function householder.
* \param n Length of A and A[i].
* \param b Vector b for Ax=b. Will be overwritten with elements of x.
* \return Status.
* */
int solve_QR(double ** A, double * alpha, int n, double * b);
/*
* \brief Computes Q^Tb and stores the result in b.
*
* \param A Matrix that has been modified by the function householder.
* \param alpha Diagonal elements of R, produced by the function householder.
* \param n Length of A and A[i].
* \param b Vector b for Ax=b. Will be overwritten with elements of the result.
*
* \return Status.
* */
int qtb(double ** A, double * alpha, int n, double * b);
/*
*
* \brief Uses backwards substitution to solve R = Q^Tb.
*
* \param A Matrix that has been modified by the function householder.
* \param alpha Diagonal elements of R, produced by the function householder.
* \param n Length of A and A[i].
* \param b Vector b for Ax=b. Will be overwritten with elements of the result.
*
* \return Status.
*
* */
int rw_subs(double ** A, double * alpha, int n, double * b);
/*
* \brief Print the matrix in a nicely formatted way to stream.
*
* \param stream The output stream.
* \param matrix The matrix to print.
* \param n Length of matrix[i].
* \param m Length of matrix.
*
* */
int fprintm(FILE * stream, double ** matrix, int n, int m);
/*
* \brief Print the vector in a nicely formatted way to stream.
*
* \param stream The output stream.
* \param vector The vector to print.
* \param n Length of vector.
*
* */
int fprintv(FILE * stream, double * vector, int n);
#define printm(matrix, n, m) fprintm(stdout, matrix, n, m)
#define printv(vector, n) fprintv(stdout, vector, n)
int main(void)
{
int status = 0;
return status;
}
int householder(double ** A, double * alpha, int n, int m)
{
int i, j;
for(i = 0; i < n; i++)
{
// Bring this column in triangular shape.
}
}