-->[L,U]=LUcho(A)                      
 A  =
 
!   4.    5.    3. !
!   3.    4.    2. !
!   2.    3.  - 1. !
pivot=4.000000
etape 1
 A  =
 
!   2.     2.5     1.5  !
!   1.5    0.25  - 0.25 !
!   1.     0.5   - 2.5  !
pivot=0.250000
etape 2
 A  =
 
!   2.     2.5    1.5 !
!   1.5    0.5  - 0.5 !
!   1.     1.   - 2.  !
pivot=-2.000000
etape 3
 A  =
 
!   2.     2.5    1.5        !
!   1.5    0.5  - 0.5        !
!   1.     1.     1.4142136i !
 U  =
 
!   2.    2.5    1.5        !
!   0     0.5  - 0.5        !
!   0     0      1.4142136i !
 L  =
 
!   2.     0      0          !
!   1.5    0.5    0          !

!   1.     1.     1.4142136i !
 
-->L*U
 ans  =
 
!   4.    5.    3. !
!   3.    4.    2. !
!   2.    3.  - 1. !
 
-->L*U-A
 ans  =
 
!   0    0    0         !
!   0    0    0         !
!   0    0    3.331E-16 !