Vector.Ln Method

Overload List

#	Signature	Description
1	function Ln: TMtxVec;	Natural logarithm.
	└ indexed: function Ln(Index: Integer; Len: Integer): TMtxVec;
2	function Ln(const X: TMtxVec): TMtxVec;	Calculate the natural algorithm for all X elements and store the results in the calling object.
	└ indexed: function Ln(const X: TMtxVec; XIndex: Integer; Index: Integer; Len: Integer): TMtxVec;

Overload 1: function Ln: TMtxVec;

Natural logarithm.

Result: stored in self (calling object), returns self for chaining

Remarks:

Calculate the natural log for all calling object elements in-place.

Examples

var a,b: Vector;
begin
    a.SetIt(False,[1,2,3,4]);
    a.Ln;    //same as:
    a := Ln(a);
    b.Ln(a); //same as:
    b := Ln(a);
end;

var
    a, expected: Vector;
begin
    a := [1.0, 2.71828182845905, 7.38905609893065, 20.0855369231877];
    a.Ln;
    expected := [0.0, 1.0, 2.0, 3.0];
    if not a.IsEqual(expected, 1e-10, TCompare.cmpAbsolute) then
        raise Exception.Create('Vector.Ln: mismatch');
end;

See Also: Vector.Exp

Indexed: function Ln(Index: Integer; Len: Integer): TMtxVec;

Calculate the natural logarithm for calling object elements [Index]..[Index+Len-1] in-place.

#	Name	Type	Description
1	Index	Integer	start index
2	Len	Integer	element count

Result: stored in self (calling object), returns self for chaining

Remarks:

An exception is raised if Vector.ConditionCheck is True and array borders are overrun.

Overload 2: function Ln(const X: TMtxVec): TMtxVec;

Calculate the natural algorithm for all X elements and store the results in the calling object.

#	Name	Type	Description
1	X	TMtxVec

Result: stored in self (calling object), returns self for chaining

Remarks:

Size and Vector.Complex properties of the calling vector are set implicitly to match the X object.

Examples

var
    a, x, expected: Vector;
begin
    x := [1.0, 2.71828182845905, 7.38905609893065, 20.0855369231877];
    a.Ln(x);
    expected := [0.0, 1.0, 2.0, 3.0];
    if not a.IsEqual(expected, 1e-10, TCompare.cmpAbsolute) then
        raise Exception.Create('Vector.Ln: mismatch');
end;

Indexed: function Ln(const X: TMtxVec; XIndex: Integer; Index: Integer; Len: Integer): TMtxVec;

Calculate the natural logarithm for X elements [XIndex]..[XIndex+Len-1].

#	Name	Type	Description
1	X	TMtxVec
2	XIndex	Integer	X start index
3	Index	Integer	start index
4	Len	Integer	element count

Result: stored in self (calling object), returns self for chaining

Remarks:

Store the results in the calling object elements [Index]..[Index+Len-1]. Size and Vector.Complex properties of the calling object must be set explicitly. An exception is raised if Vector.ConditionCheck is True and array borders are overrun.