FLA_Bidiag_UT_create_T.c File Reference

(r)

Functions
FLA_Error	FLA_Bidiag_UT_create_T (FLA_Obj A, FLA_Obj *TU, FLA_Obj *TV)

Function Documentation

FLA_Bidiag_UT_create_T()

FLA_Error FLA_Bidiag_UT_create_T	(	FLA_Obj	A,
		FLA_Obj *	TU,
		FLA_Obj *	TV
	)

{
  FLA_Datatype datatype;
  dim_t        b_alg, k;
  dim_t        rs_T, cs_T;
 
  // Query the datatype of A.
  datatype = FLA_Obj_datatype( A );
 
  // Query the blocksize from the library.
  b_alg = FLA_Query_blocksize( datatype, FLA_DIMENSION_MIN );
 
  // Scale the blocksize by a pre-set global constant.
  b_alg = ( dim_t )( ( ( double ) b_alg ) * FLA_BIDIAG_INNER_TO_OUTER_B_RATIO );
 
  // Query the minimum dimension of A.
  k = FLA_Obj_min_dim( A );
 
  b_alg = 5;
 
  // Adjust the blocksize with respect to the min-dim of A.
  b_alg = min( b_alg, k );
  
  // Figure out whether TU and TV should be row-major or column-major.
  if ( FLA_Obj_row_stride( A ) == 1 )
  {
    rs_T = 1;          
    cs_T = b_alg;      
  }
  else // if ( FLA_Obj_col_stride( A ) == 1 )
  {
    rs_T = k;
    cs_T = 1;
  }
 
  // Create two b_alg x k matrices to hold the block Householder transforms
  // that will be accumulated within the bidiagonal reduction algorithm.
  // If the matrix dimension has a zero dimension, apply_q complains it.
  if ( TU != NULL ) FLA_Obj_create( datatype, b_alg, k, rs_T, cs_T, TU );
  if ( TV != NULL ) FLA_Obj_create( datatype, b_alg, k, rs_T, cs_T, TV );
 
  return FLA_SUCCESS;
}

References FLA_Obj_create(), FLA_Obj_datatype(), FLA_Obj_min_dim(), FLA_Obj_row_stride(), FLA_Query_blocksize(), and i.

Referenced by FLA_Svd_ext_u_unb_var1(), FLA_Svd_uv_unb_var1(), and FLA_Svd_uv_unb_var2().