Functions | |
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_is_real(), FLA_Obj_length(), FLA_Part_2x2(), FLA_Repart_2x2_to_3x3(), FLA_Sqrt(), and FLA_Syr_external().
00038 { 00039 FLA_Obj ATL, ATR, A00, a01, A02, 00040 ABL, ABR, a10t, alpha11, a12t, 00041 A20, a21, A22; 00042 00043 int value = 0; 00044 00045 FLA_Part_2x2( A, &ATL, &ATR, 00046 &ABL, &ABR, 0, 0, FLA_TL ); 00047 00048 while ( FLA_Obj_length( ATL ) < FLA_Obj_length( A ) ){ 00049 00050 FLA_Repart_2x2_to_3x3( ATL, /**/ ATR, &A00, /**/ &a01, &A02, 00051 /* ************* */ /* ************************** */ 00052 &a10t, /**/ &alpha11, &a12t, 00053 ABL, /**/ ABR, &A20, /**/ &a21, &A22, 00054 1, 1, FLA_BR ); 00055 00056 /*------------------------------------------------------------*/ 00057 00058 if ( FLA_Obj_is_real( A ) ) 00059 { 00060 /* alpha11 = sqrt( alpha11 ); */ 00061 value = FLA_Sqrt( alpha11 ); 00062 00063 if ( value != FLA_SUCCESS ) 00064 return ( FLA_Obj_length( A00 ) + 1 ); 00065 00066 /* a21 = a21 / alpha11; */ 00067 FLA_Inv_scal_external( alpha11, a21 ); 00068 00069 /* A22 = A22 - a21 * a21'; */ 00070 FLA_Syr_external( FLA_LOWER_TRIANGULAR, FLA_MINUS_ONE, a21, A22 ); 00071 } 00072 else 00073 { 00074 /* alpha11 = sqrt( alpha11 ); */ 00075 value = FLA_Sqrt( alpha11 ); 00076 00077 if ( value != FLA_SUCCESS ) 00078 return ( FLA_Obj_length( A00 ) + 1 ); 00079 00080 /* a21 = a21 / alpha11; */ 00081 FLA_Inv_scal_external( alpha11, a21 ); 00082 00083 /* A22 = A22 - a21 * a21'; */ 00084 FLA_Her_external( FLA_LOWER_TRIANGULAR, FLA_MINUS_ONE, a21, A22 ); 00085 } 00086 00087 /*------------------------------------------------------------*/ 00088 00089 FLA_Cont_with_3x3_to_2x2( &ATL, /**/ &ATR, A00, a01, /**/ A02, 00090 a10t, alpha11, /**/ a12t, 00091 /* ************** */ /* ************************ */ 00092 &ABL, /**/ &ABR, A20, a21, /**/ A22, 00093 FLA_TL ); 00094 } 00095 00096 return value; 00097 }