Package hw4

Class RatPolyStack

java.lang.Object

hw4.RatPolyStack

All Implemented Interfaces:

java.lang.Iterable<RatPoly>

public final class RatPolyStack
extends java.lang.Object
implements java.lang.Iterable<RatPoly>

RatPolyStack is a mutable finite sequence of RatPoly objects.

Each RatPolyStack can be described by [p1, p2, ... ], where [] is an empty stack, [p1] is a one element stack containing the Poly 'p1', and so on. RatPolyStacks can also be described constructively, with the append operation, ':'. such that [p1]:S is the result of putting p1 at the front of the RatPolyStack S.

A finite sequence has an associated size, corresponding to the number of elements in the sequence. Thus the size of [] is 0, the size of [p1] is 1, the size of [p1, p1] is 2, and so on.

Constructor Summary

Constructors

Constructor	Description
RatPolyStack()

Method Summary

Modifier and Type	Method	Description
void	add()	Pops two elements off of the stack, adds them, and places the result on top of the stack.
void	clear()	Clears the stack.
void	differentiate()	Pops the top element off of the stack, differentiates it, and places the result on top of the stack.
void	div()	Divides the next from top poly by the top poly, pops both off the stack, and places the result on top of the stack.
void	dup()	Duplicates the top RatPoly on this.
RatPoly	getNthFromTop(int index)	Returns the RatPoly that is 'index' elements from the top of the stack.
void	integrate()	Pops the top element off of the stack, integrates it, and places the result on top of the stack.
java.util.Iterator<RatPoly>	iterator()	Returns an iterator of the elements contained in the stack.
void	mul()	Pops two elements off of the stack, multiplies them, and places the result on top of the stack.
RatPoly	pop()	Removes and returns the top RatPoly.
void	push(RatPoly p)	Pushes a RatPoly onto the top of this.
int	size()	Returns the number of RayPolys in this RatPolyStack.
void	sub()	Subtracts the top poly from the next from top poly, pops both off the stack, and places the result on top of the stack.
void	swap()	Swaps the top two elements of this.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

RatPolyStack

public RatPolyStack()

Spec.effects:

Constructs a new RatPolyStack, [].

Method Detail

size

public int size()

Returns the number of RayPolys in this RatPolyStack.

Returns:

the size of this sequence.

push

public void push(RatPoly p)

Pushes a RatPoly onto the top of this.

Parameters:

p - The RatPoly to push onto this stack.

Spec.modifies:

this

Spec.effects:

this_post = [p]:this

Spec.requires:

p != null

pop

public RatPoly pop()

Removes and returns the top RatPoly.

Returns:

p where this = [p]:S

Spec.modifies:

this

Spec.effects:

If this = [p]:S then this_post = S

Spec.requires:

this.size() > 0

dup

public void dup()

Duplicates the top RatPoly on this.

Spec.modifies:

this

Spec.effects:

If this = [p]:S then this_post = [p, p]:S

Spec.requires:

this.size() > 0

swap

public void swap()

Swaps the top two elements of this.

Spec.modifies:

this

Spec.effects:

If this = [p1, p2]:S then this_post = [p2, p1]:S

Spec.requires:

this.size() >= 2

clear

public void clear()

Clears the stack.

Spec.modifies:

this

Spec.effects:

this_post = []

getNthFromTop

public RatPoly getNthFromTop(int index)

Returns the RatPoly that is 'index' elements from the top of the stack.

Parameters:

index - The index of the RatPoly to be retrieved.

Returns:

If this = S:[p]:T where S.size() = index, then returns p.

Spec.requires:

index >= 0 & & index < this.size()

add

public void add()

Pops two elements off of the stack, adds them, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1, p2]:S then this_post = [p3]:S where p3 = p1 + p2

Spec.requires:

this.size() >= 2

sub

public void sub()

Subtracts the top poly from the next from top poly, pops both off the stack, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1, p2]:S then this_post = [p3]:S where p3 = p2 - p1

Spec.requires:

this.size() >= 2

mul

public void mul()

Pops two elements off of the stack, multiplies them, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1, p2]:S then this_post = [p3]:S where p3 = p1 * p2

Spec.requires:

this.size() >= 2

div

public void div()

Divides the next from top poly by the top poly, pops both off the stack, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1, p2]:S then this_post = [p3]:S where p3 = p2 / p1

Spec.requires:

this.size() >= 2

differentiate

public void differentiate()

Pops the top element off of the stack, differentiates it, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1]:S then this_post = [p2]:S where p2 = derivative of p1

Spec.requires:

this.size() >= 1

integrate

public void integrate()

Pops the top element off of the stack, integrates it, and places the result on top of the stack.

Spec.modifies:

this

Spec.effects:

If this = [p1]:S then this_post = [p2]:S where p2 = indefinite integral of p1 with integration constant 0

Spec.requires:

this.size() >= 1

iterator

public java.util.Iterator<RatPoly> iterator()

Returns an iterator of the elements contained in the stack.

Specified by:

iterator in interface java.lang.Iterable<RatPoly>

Returns:

an iterator of the elements contained in the stack in order from the bottom of the stack to the top of the stack.