partmap< _linetype, _valuetype > Class Template Reference

A map from a linear space to value objects. More...

#include <partmap.hh>

Public Types
typedef std::map< _linetype, _valuetype >	maptype
	Defining the map from split points to value objects.
typedef maptype::iterator	iterator
	A partmap iterator is an iterator into the map.
typedef maptype::const_iterator	const_iterator
	A constant iterator.

Public Member Functions
_valuetype &	getValue (const _linetype &pnt)
	Get the value object at a point. More...
const _valuetype &	getValue (const _linetype &pnt) const
	Get the value object at a point. More...
const _valuetype &	bounds (const _linetype &pnt, _linetype &before, _linetype &after, int &valid) const
	Get the value object for a given point and return the range over which the value object applies. More...
_valuetype &	split (const _linetype &pnt)
	Introduce a new split point. More...
_valuetype &	clearRange (const _linetype &pnt1, const _linetype &pnt2)
	Clear a range of split points. More...

Detailed Description

template<typename _linetype, typename _valuetype>
class partmap< _linetype, _valuetype >

A map from a linear space to value objects.

The partmap is a template class taking:

• _linetype which represents an element in the linear space
• _valuetype which are the objects that linear space maps to

Let R be the linear space with an ordering, and let { a_i } be a finite set of points in R. The a_i partition R into a finite number of disjoint sets { x : x < a_0 }, { x : x>=a_0 && x < a_1 }, ... { x : x>=a_i && x < a_i+1 }, ... { x : x>=a_n }

A partmap maps elements of this partition to _valuetype objects A _valuetype is then associated with any element x in R by looking up the value associated with the partition element containing x.

The map is defined by starting with a default value object that applies to the whole linear space. Then split points are introduced, one at a time, in the linear space. At each split point, the associated value object is split into two objects. At any point the value object describing some part of the linear space can be changed.

Member Function Documentation

bounds()

template<typename _linetype , typename _valuetype >

const _valuetype & partmap< _linetype, _valuetype >::bounds	(	const _linetype &	pnt,
		_linetype &	before,
		_linetype &	after,
		int &	valid
	)		const

Get the value object for a given point and return the range over which the value object applies.

Pass back a before and after point defining the maximal range over which the value applies. An additional validity code is passed back describing which of the bounding points apply:

• 0 if both bounds apply
• 1 if there is no lower bound
• 2 if there is no upper bound,
• 3 if there is neither a lower or upper bound

  Parameters

  pnt	is the given point around which to compute the range
  before	is a reference to the passed back lower bound
  after	is a reference to the passed back upper bound
  valid	is a reference to the passed back validity code

  Returns

  the corresponding value object

clearRange()

template<typename _linetype , typename _valuetype >

_valuetype & partmap< _linetype, _valuetype >::clearRange	(	const _linetype &	pnt1,
		const _linetype &	pnt2
	)

Clear a range of split points.

Split points are introduced at the two boundary points of the given range, and all split points in between are removed. The value object that was initially present at the left-most boundary point becomes the value (as a copy) for the whole range.

Parameters

pnt1	is the left-most boundary point of the range
pnt2	is the right-most boundary point

Returns

the value object assigned to the range

getValue() [1/2]

template<typename _linetype , typename _valuetype >

_valuetype & partmap< _linetype, _valuetype >::getValue

(

const _linetype &

pnt

)

Get the value object at a point.

Look up the first split point coming before the given point and return the value object it maps to. If there is no earlier split point return the default value.

Parameters

pnt	is the given point in the linear space

Returns

the corresponding value object

getValue() [2/2]

template<typename _linetype , typename _valuetype >

const _valuetype & partmap< _linetype, _valuetype >::getValue

(

const _linetype &

pnt

)

const

Get the value object at a point.

Look up the first split point coming before the given point and return the value object it maps to. If there is no earlier split point return the default value.

Parameters

pnt	is the given point in the linear space

Returns

the corresponding value object

split()

template<typename _linetype , typename _valuetype >

_valuetype & partmap< _linetype, _valuetype >::split

(

const _linetype &

pnt

)

Introduce a new split point.

Add (if not already present) a point to the linear partition.

Parameters

pnt	is the (new) point

Returns

the (possibly) new value object for the range starting at the point

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

• partmap.hh