MeanNdC - Mean in N-D space

User Documentation

RAVL, Recognition And Vision Library

MeanNdC

Mean in N-D space

include	"Ravl/MeanNd.hh"
Created:	26/05/1994
User Level:	Normal
Library:	RavlMath
In Scope:	RavlN

Comments:
The class MeanNdC serves for computation of the mean of a set of N-dimensional vectors.

Parent Classes:

VectorC

Variables:

Methods:

MeanNdC(): Default constructor.
MeanNdC(const SArray1dC<VectorC> & vecs): Caluclate the mean of an array of vectors.
All the vectors must have the same size, if the array is empty a zero mean is generated.
MeanNdC(const SizeT dim): Creat an N-dimentional mean.
Creates zero mean representing the 'n'-dimensional set containing no data points.
MeanNdC(const VectorC & mean): Create a mean with a single point.
Creates the mean vector representing the data set containing just one data point. This object is attached to the memory of 'point'.
MeanNdC(SizeT n,const VectorC & mean): Create with a mean an a number of points.
Creates the mean vector representing the data set containing 'n' points and represented by the 'mean'. This object is attached to the memory of 'mean'.
MeanNdC Copy() const: Copy this mean
Returns a new physical copy of this object.

Information about an object

SizeT Number() const: Returns number of points which were added into the object.
const VectorC & Mean() const: Returns the current value of the mean.

Object modification

void SetZero(): Reset all the counters to zero.
void Set(SizeT n,const VectorC & m): Sets the new content of mean object.
It will represent 'n' points with the mean location 'm'.
MeanNdC & operator +=(const VectorC & point): Adds a point to the set.
MeanNdC & operator -=(const VectorC & point): Removes a point from the set.
Be carefull to remove a point which was already added to the set, otherwise the representation will not describe a real set.
MeanNdC & operator +=(const MeanNdC & mean): Adds the whole set of points represented by the mean object 'm'.
MeanNdC & operator -=(const MeanNdC & mean): Removes the whole set of points represented by the mean object 'm'.
Be carefull to remove points which was already added to the set, otherwise the representation will not describe a real set.

#include "Ravl/Vector.hh"

explicit VectorC(UIntT size): Constructor.
Create a vector of 'size' elements
bool IsReal() const: Test if vector only contains real values.
This will return false if either nan's (Not an number) or infinite values are found.

#include "Ravl/TVector.hh"

explicit TVectorC(SizeT n): Constructor.
operator TFVectorC<RealT,N>(): Convert to a fixed size vector.
RealT Sum() const: Returns the sum all elements of the vector.
RealT Product() const: Returns the product of all elements of the vector.
RealT SumOfSqr() const: Returns the sum of the squares of all the elements of the vector.
RealT SumOfAbs() const: Returns the sum of the absolute values of all the elements of the vector.
RealT MaxValue() const: Largest value in the array.
RealT MaxMagintude() const: Value of the largest magnitude in the vector.
RealT MinValue() const: Smalleset value in the array.
const TVectorC<RealT> & Reciprocal(): All elements of the vector are changed to their reciprocal values. It is assumed that all elements of the vector differs from zero.
RealT Modulus() const: Returns the modulus of the vector.
The Sqrt(SumOfSqr()).
RealT TMul(const TVectorC<RealT> & b) const: multiplication 'DataT' = (*this).T() * b
RealT Dot(const TVectorC<RealT> & v) const: scalar product of vectors
const TVectorC<RealT> & SetSmallToBeZero(const RealT & min): Set values smaller than 'min' to zero in vector.
TMatrixC<RealT> OuterProduct(const TVectorC<RealT> & a) const: Calculate the outer product of this vector and a.
To use the function you must also include 'Ravl/Matrix.hh'.
TMatrixC<RealT> OuterProduct(const TVectorC<RealT> & a,RealT b) const: Calculate the outer product of this vector and a multiplied by b.
To use the function you must also include 'Ravl/Matrix.hh'.
TMatrixC<RealT> OuterProduct() const: Calculate the outer product of this vector with itself.
To use the function you must also include 'Ravl/Matrix.hh'.
TVectorC<RealT> Unit() const: Return a unit vector
const TVectorC<RealT> & MakeUnit(): Make this a unit vector.
IndexC MaxIndex() const: Find the index with the most positive valued index.
IndexC MaxAbsIndex() const: Find the index with the absolute maximum valued index.

Constructors, assigment, and destructor

#include "Ravl/SArray1d.hh"

SArray1dC<RealT> Copy() const: Creates a new physical copy of the array.
SArray1dC<RealT> Copy(UIntT extend) const: Creates a new physical copy of the array.
'extend' extra elements initalised by the default constuctor are appended to the end of the array.
void CopyFrom(const Slice1dC<RealT> & slice): Copy contents of slice into array.
The first element of the slice is copied to element 0 of this array, second to 1 etc. If this array isn't large enough an exception is thrown.
const SArray1dC<RealT> & operator =(const SArray1dC<RealT> & vv): Assign this handle to the data in VV.
SArray1dC<RealT> operator +(const SArray1dC<RealT> & arr) const: Sums 2 numerical arrays.
The operator returns the result as a new array.
SArray1dC<RealT> operator -(const SArray1dC<RealT> & arr) const: Subtract 2 numerical arrays.
The operator returns the result as a new array.
SArray1dC<RealT> operator *(const SArray1dC<RealT> & arr) const: Mutliplies 2 numerical arrays.
The operator returns the result as a new array.
SArray1dC<RealT> operator /(const SArray1dC<RealT> & arr) const: Divides 2 numerical arrays.
The operator returns the result as a new array.
SArray1dC<RealT> operator *(const RealT & number) const: Multiplys the array by the 'number'.
The operator returns the result as a new array.
SArray1dC<RealT> operator /(const RealT & number) const: Divides all array items by the 'number'.
The operator returns the result as a new array.
SArray1dC<RealT> operator +(const RealT & number) const: Adds 'number' to the array.
The operator returns the result as a new array.
SArray1dC<RealT> operator -(const RealT & number) const: Subtracts 'number' from all array items.
The operator returns the result as a new array.
const SArray1dC<RealT> & operator +=(const SArray1dC<RealT> & arr): Adds the 2nd array to this array.
const SArray1dC<RealT> & operator -=(const SArray1dC<RealT> & arr): Subtracts the 2nd array from this array.
const SArray1dC<RealT> & operator *=(const SArray1dC<RealT> & arr): Multiplies the 2nd array to this array.
const SArray1dC<RealT> & operator /=(const SArray1dC<RealT> & arr): Divides the 2nd array from this array.
const SArray1dC<RealT> & operator +=(const RealT & number): Adds 'number' to all array items.
const SArray1dC<RealT> & operator -=(const RealT & number): Subtracts 'number' from all array items.
const SArray1dC<RealT> & operator *=(const RealT & number): Multiplies the array by the 'number'.
const SArray1dC<RealT> & operator /=(const RealT & number): Divides the array elements by the 'number'.
RealT Sum() const: Calculate the sum of all elements in the array
RealT SumSqr() const: Calculate the sum of the squares of all elements in the array

Access to the object and its parts.

const SArray1dC<RealT> & SArray1d() const: Access to the whole constant array.
SArray1dC<RealT> & SArray1d(): Access to the whole array.
Slice1dC<RealT> Slice1d(): Access array as a slice.

Modifications of the representation

SArray1dC<RealT> & Append(const SArray1dC<RealT> & a): This array is extended by the length of the array 'a' and the contents of both arrays are copied to it. Empty arrays are handled correctly.
SArray1dC<RealT> Join(const SArray1dC<RealT> & Oth) const: Join this Array and another into a new Array which is returned. This does not change either of its arguments. This is placed in the array first, followed by 'Oth'.
SArray1dC<RealT> From(UIntT offset): Return array from offset to the end of the array.
If offset is larger than the array an empty array is returned,
SArray1dC<RealT> From(UIntT offset,UIntT size): Return array from offset to the end of the array.
If offset is larger than the array an empty array is returned,
SArray1dC<RealT> After(UIntT offset): Return array after offset to the end of the array.
If offset is larger than the array an empty array is returned,

Special operations

BufferC<RealT> & Buffer(): Access base data buffer.
Experts only.
const BufferC<RealT> & Buffer() const: Constant access base data buffer.
Experts only.
void Sort(): Sort the array in place.
This does a simple bubble sort. FIXME:- we could do with something better!
bool operator ==(const SArray1dC<RealT> & vv): Comparison operator
Returns true if the two arrays are the same length and their contents are identical.
UIntT Hash() const: Compute a hash value for the array.
RealT * DataStart() const: Returns the address of element 0.
If the array has zero length a null pointer may be returned.

#include "Ravl/SBfAcc.hh"

const SizeBufferAccessC<RealT> & operator =(RealT * bp): Changes the reference element to the element pointed by 'bp'. Access to the object --------------------
RealT * DataStart() const: Returns the address of the first element of the buffer.
SizeT Size() const: Returns the number of elements of the array.
IndexRangeC Limits() const: Returns the usable range of indeces expressed by this object.
IndexRangeC Range() const: Returns the usable range of indeces expressed by this object.
IndexC IMin() const: Returns the minimum index of the range of this access.
IndexC IMax() const: Returns the maximum index of the range of this access.
const RealT & operator [](const IndexC i) const: Read-only access to the ('i'+1)-th element of the buffer.
RealT & operator [](const IndexC i): Read-write access to the ('i'+1)-th element of the buffer.
const SizeBufferAccessC<RealT> & SAccess(void) const: Returns this object. Logical functions -----------------
bool IsEmpty() const: Returns TRUE if the size of the array is zero.
bool Contains(IndexC i) const: Returns TRUE if the array contains an item with the index 'i'. Modifications of the access ---------------------------
SizeT ShrinkHigh(SizeT k): Changes the number of elements by subtracting the last 'k' elements.
const SizeBufferAccessC<RealT> & Swap(SizeBufferAccessC<RealT> & a): Exchanges the contents of this buffer with buffer 'a'.
void Attach(const SizeBufferAccessC<RealT> & b): Changes this buffer access to have the same access rights as 'b'.
void Attach(const BufferAccessC<RealT> & b,SizeT size): Changes this buffer access to have the access rights as 'b' limited for 'size' elements.
SizeBufferAccessC<RealT> operator +(SizeT i) const: Creates the new access object shifted 'i' elements to the right (towards next elements). The size is descreased to fit the the original range of this access. Modifications of the buffer contents ------------------------------------
void Fill(const RealT & d): 'd' value is assigned to all elements of the buffer.
void CopyFrom(const SizeBufferAccessC<RealT> & oth): Copy contents of another buffer into this one.
NB. Buffers MUST be the same length.
void Reverse(): Reverse the order of elements in this array in place.
SizeBufferAccessC<RealT> BufferFrom(UIntT first): Get an access for this buffer starting from the 'first' element to the end of the buffer.
SizeBufferAccessC<RealT> BufferFrom(UIntT first,UIntT len): Get an access for this buffer starting from the 'first' element for 'len' elements.
An error will be generated if the requested buffer isn't contains within this one.
bool operator ==(const SizeBufferAccessC<RealT> & ba) const: Are two accesses the same ?

#include "Ravl/BufferAccess.hh"

RealT * ReferenceElm() const: Returns the pointer to the reference element of the attached buffer. The reference element need not to be the valid element of the buffer.
void * ReferenceVoid() const: Returns the pointer to the reference element of the attached buffer. The reference element need not to be the valid element of the buffer. The function is intended to be used in printing.
bool IsValid() const: Returns TRUE if this buffer access is not a default access object.
const RealT & operator [](const IndexC i) const: Read-only access to the ('i'+1)-th element of the buffer.
RealT & operator [](const IndexC i): Read-write access to the ('i'+1)-th element of the buffer.
const BufferAccessC<RealT> & operator +=(IndexC ind): Inplace Add index to start position.
const BufferAccessC<RealT> & operator -=(IndexC ind): Inplace Subtract index from start position.
BufferAccessC<RealT> operator -(IndexC ind) const: Substract value from position, and return it as a new value.
BufferAccessC<RealT> operator +(IndexC ind) const: Substract value from position, and return it as a new value.
bool operator ==(const BufferAccessC<RealT> & ba) const: Are two accesses the same ?
bool operator !=(const BufferAccessC<RealT> & ba) const: Are two accesses the same ?

Maintainer:Radek Marik, Created: 26/05/1994, Documentation by CxxDoc: Tue Aug 13 09:59:02 2002