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Functions
FLA_Chol_l_unb_var3.c File Reference

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Functions

FLA_Error FLA_Chol_l_unb_var3 (FLA_Obj A)
 

Function Documentation

◆ FLA_Chol_l_unb_var3()

FLA_Error FLA_Chol_l_unb_var3 ( FLA_Obj  A)

References FLA_Cont_with_3x3_to_2x2(), FLA_Her_external(), FLA_Inv_scal_external(), FLA_MINUS_ONE, FLA_Obj_length(), FLA_Part_2x2(), FLA_Repart_2x2_to_3x3(), and FLA_Sqrt().

Referenced by FLA_Chol_l().

16 {
17  FLA_Obj ATL, ATR, A00, a01, A02,
18  ABL, ABR, a10t, alpha11, a12t,
19  A20, a21, A22;
20 
21  int r_val = FLA_SUCCESS;
22 
23  FLA_Part_2x2( A, &ATL, &ATR,
24  &ABL, &ABR, 0, 0, FLA_TL );
25 
26  while ( FLA_Obj_length( ATL ) < FLA_Obj_length( A ) ){
27 
28  FLA_Repart_2x2_to_3x3( ATL, /**/ ATR, &A00, /**/ &a01, &A02,
29  /* ************* */ /* ************************** */
30  &a10t, /**/ &alpha11, &a12t,
31  ABL, /**/ ABR, &A20, /**/ &a21, &A22,
32  1, 1, FLA_BR );
33 
34  /*------------------------------------------------------------*/
35 
36  // alpha11 = sqrt( alpha11 )
37  r_val = FLA_Sqrt( alpha11 );
38 
39  if ( r_val != FLA_SUCCESS )
40  return ( FLA_Obj_length( A00 ) );
41 
42  // a21 = a21 / alpha11
43  FLA_Inv_scal_external( alpha11, a21 );
44 
45  // A22 = A22 - a21 * a21'
46  FLA_Her_external( FLA_LOWER_TRIANGULAR, FLA_MINUS_ONE, a21, A22 );
47 
48  /*------------------------------------------------------------*/
49 
50  FLA_Cont_with_3x3_to_2x2( &ATL, /**/ &ATR, A00, a01, /**/ A02,
51  a10t, alpha11, /**/ a12t,
52  /* ************** */ /* ************************ */
53  &ABL, /**/ &ABR, A20, a21, /**/ A22,
54  FLA_TL );
55  }
56 
57  return r_val;
58 }
FLA_Error FLA_Her_external(FLA_Uplo uplo, FLA_Obj alpha, FLA_Obj x, FLA_Obj A)
Definition: FLA_Her_external.c:13
FLA_Error FLA_Inv_scal_external(FLA_Obj alpha, FLA_Obj A)
Definition: FLA_Inv_scal_external.c:13
FLA_Obj FLA_MINUS_ONE
Definition: FLA_Init.c:22
FLA_Error FLA_Repart_2x2_to_3x3(FLA_Obj ATL, FLA_Obj ATR, FLA_Obj *A00, FLA_Obj *A01, FLA_Obj *A02, FLA_Obj *A10, FLA_Obj *A11, FLA_Obj *A12, FLA_Obj ABL, FLA_Obj ABR, FLA_Obj *A20, FLA_Obj *A21, FLA_Obj *A22, dim_t mb, dim_t nb, FLA_Quadrant quadrant)
Definition: FLA_View.c:142
FLA_Error FLA_Part_2x2(FLA_Obj A, FLA_Obj *A11, FLA_Obj *A12, FLA_Obj *A21, FLA_Obj *A22, dim_t mb, dim_t nb, FLA_Quadrant quadrant)
Definition: FLA_View.c:17
Definition: FLA_type_defs.h:158
FLA_Error FLA_Cont_with_3x3_to_2x2(FLA_Obj *ATL, FLA_Obj *ATR, FLA_Obj A00, FLA_Obj A01, FLA_Obj A02, FLA_Obj A10, FLA_Obj A11, FLA_Obj A12, FLA_Obj *ABL, FLA_Obj *ABR, FLA_Obj A20, FLA_Obj A21, FLA_Obj A22, FLA_Quadrant quadrant)
Definition: FLA_View.c:304
FLA_Error FLA_Sqrt(FLA_Obj alpha)
Definition: FLA_Sqrt.c:13
dim_t FLA_Obj_length(FLA_Obj obj)
Definition: FLA_Query.c:116