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SOLIPSYST Library "JINRLIB" F098
Author: A.P.Sapojnikov
Language: Fortran
GORDAN METHOD FOR A LINEAR SYSTEM SOLVING
The function SOLIPSYST solves a system of linear equations A * X = B
of a general type by Gordan method with a choice of the pivot element
in the column.
Structure:
----------
Type: FUNCTION
User Entry Names: SOLIPSYST
Usage:
------
DETERM = SOLIPSYST (A, N, M)
At the input:
A - (REAL*8) matrix dimension (N, N+M+1),
containing in the first N columns the coefficients of A system,
in the next M columns - M sets of the right parts B,
last column - working;
N - (INTEGER) system dimension (2,3...);
M - (INTEGER) number of right parts (0,1,2...).
At the output:
The first N columns of matrix A contains a inverse matrix,
the next M columns - corresponding M system solutions.
At M=0 only the inverse matrix is calculated.
The result given out by the function, is equal to a determinant
of the system or 0, if the initial matrix is singular.
Notes:
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Inside the program the file A is used as a 1D one!
Example:
--------
. . .
IMPLICIT REAL*8 (A-H,O-Z)
DIMENSION A(3,6)
DATA A/1.D0,4.D0,0.D0, 2.D0,5.D0,7.D0, 3.D0,6.D0,8.D0,
* 6.D0,15.D0,15.D0, 12.D0,30.D0,30.D0, 0.D0,0.D0,0.D0/
WRITE(*,*) ' DETERM=',SOLIPSYST(A,3,2)
DO J=4,5
WRITE(*,*) (A(I,J),I=1,3)
ENDDO
. . .
Result:
-------
DETERM= 18.000000000000000
1.000000000000000 1.000000000000000 1.000000000000000
2.000000000000000 2.000000000000000 2.000000000000000
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