HelperExtensions

Full name Microsoft.VisualBasic.Math.LinearAlgebra.HelperExtensions Assembly Microsoft.VisualBasic.Math.Core Members 8

01 Syntax

Microsoft.VisualBasic.Math.LinearAlgebra.HelperExtensions

02 Methods

Name	Overloads	Summary
GetColumn	1	从二维数组中提取指定的一列
IsNaNImaginary	1	get a logical vector for indicates that which elements inside the given numeric vector is invalid number, like NaN, Inf
NAremove	1	removes all invalid number from the given numeric vector data
PrimitiveLinearEquation	1	返回一元一次方程
Tangent	1
jaccard_coeff	2	Compute jaccard coefficient between nearest-neighbor sets Weights of both i->j and j->i are recorded if they have intersection.
JaccardIndex	1

03 Members

method GetColumn #

GetColumn(Double[0:,0:], Int32)

从二维数组中提取指定的一列

Parameters

Name	Type	Description
`matrix`	`Double[0:,0:]`	二维矩阵
`columnIndex`	`Int32`	要提取的列索引（0表示第一列）

Returns

包含该列数据的一维数组

method IsNaNImaginary #

IsNaNImaginary(IEnumerable(Of Double))

get a logical vector for indicates that which elements inside the given numeric vector is invalid number, like NaN, Inf

Parameters

Name	Type	Description
`v`	`IEnumerable(Of Double)`	-

method NAremove #

NAremove(IEnumerable(Of Double))

removes all invalid number from the given numeric vector data

Parameters

Name	Type	Description
`x`	`IEnumerable(Of Double)`	-

method PrimitiveLinearEquation #

PrimitiveLinearEquation(PointF, PointF)

返回一元一次方程

Parameters

Name	Type	Description
`p1`	`PointF`	-
`p2`	`PointF`	-

Returns

y=ax+b

method Tangent #

Tangent(SlideWindow(Of PointF))

Parameters

Name	Type	Description
`slideWindows`	`SlideWindow(Of PointF)`	Just contains two points.

method jaccard_coeff #

jaccard_coeff(Int32()(), Boolean)

Compute jaccard coefficient between nearest-neighbor sets

Weights of both i->j and j->i are recorded if they have intersection. In this case w(i->j) should be equal to w(j->i). In some case i->j has weights while j<-i has no intersections, only w(i->j) Is recorded. This Is determinded in code if(u>0). In this way, the undirected graph Is symmetrized by halfing the weight in code weights(r, 2) = u/(2.0*ncol - u)/2.

Parameters

Name	Type	Description
`idx`	`Int32()()`	-

Returns

the weight value of this function will affects by the symmetrize parameters, when

symmetrize = TRUE(default), weight in value range (0, 0.5],
FALSE, weight in value range (0, 1].

method jaccard_coeff overload 2 #

jaccard_coeff(String(), String(), Boolean)

Evaluate the jaccard coeff between two dataset

Parameters

Name	Type	Description
`a`	`String()`	-
`b`	`String()`	-
`symmetrize`	`Boolean`	-

method JaccardIndex #

JaccardIndex(Double(), Double())

Remarks

use common non-zero index as intersect

Parameters

Name	Type	Description
`x`	`Double()`	-
`y`	`Double()`	-