Package de.tilman_neumann.jml.base

Class BigIntTriangle

java.lang.Object

de.tilman_neumann.jml.base.BigIntTriangle

Direct Known Subclasses:

EgyptianFractionsTriangle

public class BigIntTriangle
extends Object

A triangle of integers.

Author:

Tilman Neumann

Constructor Summary

Constructors

Constructor	Description
BigIntTriangle()	Create a triangle without data.
BigIntTriangle(int n, BigInteger init)	Creates an initialized number triangle with n rows.

Method Summary

Modifier and Type	Method	Description
void	addRow(ArrayList<BigInteger> row)
BigInteger	get(int n, int k)	Returns the entry T[n,k], with T[1,1] being the very first element.
ArrayList<BigInteger>	getRow(int n)	return n.th row, where the first row has index 1.
BigInteger	getRowSum(int n)	Returns the sum over all entries of the n.th row, where the first row has index 1.
ArrayList<BigInteger>	getRowSums()
void	set(int n, int k, BigInteger value)	Sets the value T[n,k].
ArrayList<BigInteger>	toList()
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

BigIntTriangle

public BigIntTriangle()

Create a triangle without data. Rows may be added with the addRow() method.

BigIntTriangle

public BigIntTriangle(int n,
                      BigInteger init)

Creates an initialized number triangle with n rows.

Parameters:

n -

init - The value with which the triangle entries are initialized.

Method Detail

get

public BigInteger get(int n,
                      int k)

Returns the entry T[n,k], with T[1,1] being the very first element.

Parameters:

n -

k -

Returns:

T[n,k]

set

public void set(int n,
                int k,
                BigInteger value)

Sets the value T[n,k].

Parameters:

n -

k -

value -

addRow

public void addRow(ArrayList<BigInteger> row)

getRow

public ArrayList<BigInteger> getRow(int n)

return n.th row, where the first row has index 1.

Parameters:

n -

Returns:

n.th row

getRowSum

public BigInteger getRowSum(int n)

Returns the sum over all entries of the n.th row, where the first row has index 1.

Parameters:

n -

Returns:

the sum over all entries of the n.th row

getRowSums

public ArrayList<BigInteger> getRowSums()

Returns:

List of row sums of this triangle.

toList

public ArrayList<BigInteger> toList()

Returns:

This triangle converted into a list read by rows. Better suited for OEIS lookups.

toString

public String toString()

Overrides:

toString in class Object