Epetra_Util Class Reference

Epetra_Util: The Epetra Util Wrapper Class. More...

#include <Epetra_Util.h>

List of all members.

Public Member Functions
	Epetra_Util ()
	Epetra_Util Constructor.
	Epetra_Util (const Epetra_Util &Util)
	Epetra_Util Copy Constructor.
virtual	~Epetra_Util ()
	Epetra_Util Destructor.
Random number utilities
unsigned int	RandomInt ()
	Returns a random integer on the interval (0, 2^31-1).
double	RandomDouble ()
	Returns a random double on the interval (-1.0,1.0).
unsigned int	Seed () const
	Get seed from Random function.
int	SetSeed (unsigned int Seed)
	Set seed for Random function.
Static Public Member Functions
void	Sort (bool SortAscending, int NumKeys, int *Keys, int NumDoubleCompanions, double **DoubleCompanions, int NumIntCompanions, int **IntCompanions)
	Epetra_Util Sort Routine (Shell sort).
Epetra_Map	Create_Root_Map (const Epetra_Map &usermap, int root=0)
	Epetra_Util Create_Root_Map function.
Epetra_Map	Create_OneToOne_Map (const Epetra_Map &usermap, bool high_rank_proc_owns_shared=false)
	Epetra_Util Create_OneToOne_Map function.
Epetra_BlockMap	Create_OneToOne_BlockMap (const Epetra_BlockMap &usermap, bool high_rank_proc_owns_shared=false)
	Epetra_Util Create_OneToOne_Map function.
double	Chop (const double &Value)
	Epetra_Util Chop method. Return zero if input Value is less than ChopValue.
Static Public Attributes
const double	chopVal_

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Detailed Description

Epetra_Util: The Epetra Util Wrapper Class.

The Epetra_Util class is a collection of useful functions that cut across a broad set of other classes.

• A random number generator is provided, along with methods to set and retrieve the random-number seed.

  The random number generator is a multiplicative linear congruential generator, with multiplier 16807 and modulus 2^31 - 1. It is based on the algorithm described in "Random Number Generators: Good Ones Are Hard To Find", S. K. Park and K. W. Miller, Communications of the ACM, vol. 31, no. 10, pp. 1192-1201.

• Sorting is provided by a static function on this class (i.e., it is not necessary to construct an instance of this class to use the Sort function).

• A static function is provided for creating a new Epetra_Map object with 1-to-1 ownership of entries from an existing map which may have entries that appear on multiple processors.

Epetra_Util is a serial interface only. This is appropriate since the standard utilities are only specified for serial execution (or shared memory parallel).

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Constructor & Destructor Documentation

Epetra_Util::Epetra_Util (   )  [inline]

Epetra_Util Constructor. Builds an instance of a serial Util object.

Epetra_Util::Epetra_Util (  const Epetra_Util &  Util  )  [inline]

Epetra_Util Copy Constructor. Makes an exact copy of an existing Epetra_Util instance.

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Member Function Documentation

Epetra_BlockMap Epetra_Util::Create_OneToOne_BlockMap (  const Epetra_BlockMap &  usermap, bool  high_rank_proc_owns_shared = false )  [static]

Epetra_Util Create_OneToOne_Map function. Function to create a new Epetra_Map object with 1-to-1 ownership of entries from an existing map which may have entries that appear on multiple processors.

Epetra_Map Epetra_Util::Create_OneToOne_Map (  const Epetra_Map &  usermap, bool  high_rank_proc_owns_shared = false )  [static]

Epetra_Util Create_OneToOne_Map function. Function to create a new Epetra_Map object with 1-to-1 ownership of entries from an existing map which may have entries that appear on multiple processors.

Epetra_Map Epetra_Util::Create_Root_Map (  const Epetra_Map &  usermap, int  root = 0 )  [static]

Epetra_Util Create_Root_Map function. Function to create a new Epetra_Map object with all GIDs sent to the root processor which is zero by default. All all processors will have no GIDs. This root map can then be used to create an importer or exporter that will migrate all data to the root processor. If root is set to -1 then the user map will be replicated completely on all processors.

unsigned int Epetra_Util::Seed (   )  const

Get seed from Random function. Returns: Current random number seed.

int Epetra_Util::SetSeed (  unsigned int  Seed  )

Set seed for Random function. Parameters: In  Seed - An integer on the interval [0, INT_MAX). Returns: Integer error code, set to 0 if successful.

void Epetra_Util::Sort (  bool  SortAscending, int  NumKeys, int *  Keys, int  NumDoubleCompanions, double **  DoubleCompanions, int  NumIntCompanions, int **  IntCompanions )  [static]

Epetra_Util Sort Routine (Shell sort). This function sorts a list of integer values in ascending or descending order. Additionally it sorts any number of companion lists of doubles or ints. A shell sort is used, which is fast if indices are already sorted. Parameters: In  SortAscending - Sort keys in ascending order if true, otherwise sort in descending order.. In  NumKeys - Number of integer values to be sorted. In/Out  Keys - List of integers to be sorted. In  NumDoubleCompanions - Number of lists of double precision numbers to be sorted with the key. If set to zero, DoubleCompanions is ignored and can be set to zero. In  DoubleCompanions - DoubleCompanions[i] is a pointer to the ith list of doubles to be sorted with key. In  NumIntCompanions - Number of lists of integers to be sorted with the key. If set to zero, IntCompanions is ignored and can be set to zero. In  IntCompanions - IntCompanions[i] is a pointer to the ith list of integers to be sorted with key.

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The documentation for this class was generated from the following file:

• Epetra_Util.h

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