TMtx.Skewness Method

Double Skewness(Double AMean, Double AStdDev)

Skewness (third central momentum).

#	Name	Type	Description
1	AMean	Double	pre-computed mean
2	AStdDev	Double	output std deviation

Returns: Double

Remarks:

Calculate the calling object skewness by using mean value AMean and standard deviation AStdDev. Skewness is the third central moment, divided by third power of standard deviation:

\text{Skewness}=\frac{1}{\sigma ^3} \sum _{k=0} ^{\text{Length}-1}\left( V[k] -\langle V\rangle \right)^3 ,\quad \text{where } \langle V \rangle = \text{mean value}

Examples

Matrix a;
double c;
double d;
a.SetIt(1,4,false,new double[] {1,2,3,4});
d = a.Mean;
c = a.Skewness(d, a.StdDev(d)); //or

d = Mean(a);
c = Skewness(a, d, StdDev(a, d));

Indexed: Double Skewness(Double AMean, Double AStdDev, Int32 Index, Int32 Len)

Calculate the skewness for elements [Index]..[Index+Len-1].

#	Name	Type	Description
1	AMean	Double	pre-computed mean
2	AStdDev	Double	output std deviation
3	Index	Int32	start index
4	Len	Int32	element count

Returns: Double

Remarks:

An exception is raised if Dew.Math.TMtxVecBase.ConditionCheck is True and array borders are overrun. The AMean and AStdDev parameters must be computed from the same elements from which the Skewness is to be computed.