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Functions
FLASH_LQ_UT_solve.c File Reference

(r)

Functions

FLA_Error FLASH_LQ_UT_solve (FLA_Obj A, FLA_Obj T, FLA_Obj B, FLA_Obj X)

Function Documentation

FLA_Error FLASH_LQ_UT_solve ( FLA_Obj  A,
FLA_Obj  T,
FLA_Obj  B,
FLA_Obj  X 
)

References FLA_Check_error_level(), FLA_LQ_UT_solve_check(), FLA_Obj_length(), FLA_ONE, FLA_Part_1x2(), FLA_Part_2x1(), FLA_ZERO, FLASH_Apply_Q_UT(), FLASH_Apply_Q_UT_create_workspace(), FLASH_Copy(), FLASH_Obj_free(), FLASH_Obj_set_to_scalar(), and FLASH_Trsm().

{
  FLA_Obj W;
  FLA_Obj AL, AR;
  FLA_Obj XT, XB;

  // Check parameters.
  if ( FLA_Check_error_level() >= FLA_MIN_ERROR_CHECKING )
    FLA_LQ_UT_solve_check( A, T, B, X );

  FLASH_Apply_Q_UT_create_workspace( T, X, &W );

  FLA_Part_1x2( A,   &AL, &AR,    FLA_Obj_length( A ), FLA_LEFT );
  FLA_Part_2x1( X,   &XT,
                     &XB,    FLA_Obj_length( B ), FLA_TOP );

  FLASH_Copy( B, XT );

  FLASH_Trsm( FLA_LEFT, FLA_LOWER_TRIANGULAR, FLA_NO_TRANSPOSE,
              FLA_NONUNIT_DIAG, FLA_ONE, AL, XT );

  FLASH_Obj_set_to_scalar( FLA_ZERO, XB );

  FLASH_Apply_Q_UT( FLA_LEFT, FLA_NO_TRANSPOSE, FLA_FORWARD, FLA_ROWWISE,
                    A, T, W, X );

  FLASH_Obj_free( &W );

  return FLA_SUCCESS;
}