ludecomp_module.f90

Path: sosi/ludecomp_module.f90
Last Update: 2018-03-04 19:06:02 +0900

****************************************************************************** subroutine ludecomp ******************************************************************************

    Arrangement of array elements

 A x = b
         a(1,1)  a(1,2)  a(1,3)  a(1,4) ...  a(1,n)  |   x(1)  |   b(1)
         a(2,1)  a(2,2)  a(2,3)  a(2,4) ...  a(2,n)  |   x(2)  |   b(2)
         a(3,1)  a(3,2)  a(3,3)  a(3,4) ...  a(3,n)  |   x(3)  |   b(3)
         a(4,1)  a(4,2)  a(4,3)  a(4,4) ...  a(4,n)  |   x(4)  |   b(4)
         a(5,1)  a(5,2)  a(5,3)  a(5,4) ...  a(5,n)  |   x(5)  |   b(5)
         ...     ...     ...     ...    ...  ...     |   ...   |   ...
         a(n,1)  a(n,2)  a(n,3)  a(n,4) ...  a(n,n)  |   x(n)  |   b(n)

 A = L * U
         a(1,1)  a(1,2)  a(1,3)  a(1,4) ...  a(1,n)
         a(2,1)  a(2,2)  a(2,3)  a(2,4) ...  a(2,n)
         a(3,1)  a(3,2)  a(3,3)  a(3,4) ...  a(3,n)
         a(4,1)  a(4,2)  a(4,3)  a(4,4) ...  a(4,n)
         a(5,1)  a(5,2)  a(5,3)  a(5,4) ...  a(5,n)
         ...     ...     ...     ...    ...  ...
         a(n,1)  a(n,2)  a(n,3)  a(n,4) ...  a(n,n)

 matrix L
         1       0       0       0      ...  0
         a(2,1)  1       0       0      ...  0
         a(3,1)  a(3,2)  1       0      ...  0
         a(4,1)  a(4,2)  a(4,3)  1      ...  0
         a(5,1)  a(5,2)  a(5,3)  a(5,4) ...  0
         ...     ...     ...     ...    ...  ...
         a(n,1)  a(n,2)  a(n,3)  a(n,4) ...  a(n,n)

 matrix L
         a(1,1)  a(1,2)  a(1,3)  a(1,4) ...  a(1,n)
         0       a(2,2)  a(2,3)  a(2,4) ...  a(2,n)
         0       0       a(3,3)  a(3,4) ...  a(3,n)
         0       0       0       a(4,4) ...  a(4,n)
         0       0       0       0      ...  a(5,n)
         ...     ...     ...     ...    ...  ...
         0       0       0       0      ...  a(n,n)

******************************************************************************

This file provides the following module.