SpecialFuncs.Besi Method

Overload List

#SignatureDescription
1function Besi(NU: Double; Z: TCplx): TCplx;Modified Bessel function of the first kind, complex argument: I_(nu)(z).
2procedure Besi(NU: Double; const Z: TCplx; const resCY: TVec; Scale: Boolean);Sequence of modified Bessel functions of the first kind, complex argument: I_(nu+i)(z), i=0... N-1.
3function Besi(NU: Double; Z: TCplx; Scale: Boolean): TCplx;Modified Bessel function of the first kind, complex argument, optional scaling: I_(nu)(z).
4function Besi(NU: Double; A: Double): TCplx;Modified Bessel function of the first kind, real argument: I_(nu)(x).
5function Besi(NU: Double; A: Double; Scale: Boolean): TCplx;Modified Bessel function of the first kind, real argument, optional scaling: I_(nu)(x).
6function Besi(NU: Single; Z: TSCplx): TSCplx;
7function Besi(NU: Single; Z: TSCplx; Scale: Boolean): TSCplx;
8function Besi(NU: Single; A: Single): TSCplx;
9function Besi(NU: Single; A: Single; Scale: Boolean): TSCplx;

Overload 1: function Besi(NU: Double; Z: TCplx): TCplx;

Modified Bessel function of the first kind, complex argument: I_(nu)(z).

#NameDescription
1NUDefines the order of In(Z).
2ZDefines complex value for which In(Z) should be evaluated.

Returns: TCplx (complex) - I_(nu)(z), the modified Bessel function of the first kind of order NU at the complex argument Z.

Remarks:

I_(nu) solves the modified Bessel equation z^2 w'' + z w' - (z^2+nu^2)w = 0 and is regular at the origin: I_(nu)(z) = sum_(m=0)^(inf)1/(m! Gamma(m+nu+1))(z/2)^(2m+nu)

Domain. Any finite complex Z; order NU any real value.

Overload 2: procedure Besi(NU: Double; const Z: TCplx; const resCY: TVec; Scale: Boolean);

Sequence of modified Bessel functions of the first kind, complex argument: I_(nu+i)(z), i=0... N-1.

#NameDescription
1ZDefines complex value for which In(Z) should be evaluated.
2NUDefines the order of the Bessel function of the first kind In.
3ScaleIf Scale parameter is true, In(Z) is multiplied by e^(-|Re z|).
4resCYContains result on output and needs to be sized to desired N on input. The result holds: cyRes[j] = I(NU + j, Z)*Exp(-|Re(A)|) when scaled and cyRes[j] = I(NU + j, Z) otherwise.

Result: stored in self (calling object)

Returns: Fills with I_(nu+i)(z) for i=0,...,N-1 (N = input length of ). When is true each element is multiplied by e^(-|Re z|).

Remarks:

resCY[i] = e^(-|Re z|) I_(nu+i)(z), i=0,...,N-1, with the factor applied only when scaling is enabled. Domain. resCY must be a non-empty complex double vector.

Overload 3: function Besi(NU: Double; Z: TCplx; Scale: Boolean): TCplx;

Modified Bessel function of the first kind, complex argument, optional scaling: I_(nu)(z).

#NameDescription
1ZDefines complex value for which In(Z) should be evaluated.
2NUDefines the order of the Bessel function of the first kind In.
3ScaleIf Scale parameter is true, In(Z) is multiplied by e^(-|Re z|).

Returns: TCplx (complex) - I_(nu)(z) of order NU. When is true the result is multiplied by e^(-|Re z|), i.e. e^(-|Re z|) I_(nu)(z), which removes the exponential growth for large Re z.

Remarks:

I_(nu)(z) = sum_(m=0)^(inf)1/(m! Gamma(m+nu+1))(z/2)^(2m+nu)

Domain. Any finite complex Z; order NU any real value.

See Also: SpecialFuncs.Airy, SpecialFuncs.Biry, SpecialFuncs.Besh, SpecialFuncs.Besy, SpecialFuncs.Besj, SpecialFuncs.Besk, SpecialFuncs.EllipComplete, SpecialFuncs.EllipJacoby

Overload 4: function Besi(NU: Double; A: Double): TCplx;

Modified Bessel function of the first kind, real argument: I_(nu)(x).

#NameDescription
1NUDefines the order of In(A).
2ADefines real value for which In(A) should be evaluated.

Returns: TCplx (complex) - I_(nu)(x) of order NU at the real argument A, returned as a TCplx (imaginary part zero for x >= 0).

Remarks:

I_(nu)(x) = sum_(m=0)^(inf)1/(m! Gamma(m+nu+1))(x/2)^(2m+nu) Domain. Any finite real A; order NU any real value.

Overload 5: function Besi(NU: Double; A: Double; Scale: Boolean): TCplx;

Modified Bessel function of the first kind, real argument, optional scaling: I_(nu)(x).

#NameDescription
1ADefines real value for which In(A) should be evaluated.
2NUDefines the order of the Bessel function of the first kind In.
3ScaleIf Scale parameter is true, In(A) is multiplied by e^(-|Re x|).

Returns: TCplx (complex) - I_(nu)(x) of order NU; when is true it is multiplied by e^(-|x|).

Remarks:

Domain. Any finite real A; order NU any real value.

Overload 6: function Besi(NU: Single; Z: TSCplx): TSCplx;

#NameTypeDescription
1NUSinglescalar
2ZTSCplxscalar

Returns: TSCplx

Overload 7: function Besi(NU: Single; Z: TSCplx; Scale: Boolean): TSCplx;

#NameTypeDescription
1NUSinglescalar
2ZTSCplxscalar
3ScaleBoolean

Returns: TSCplx

Overload 8: function Besi(NU: Single; A: Single): TSCplx;

#NameTypeDescription
1NUSinglescalar
2ASinglescalar

Returns: TSCplx

Overload 9: function Besi(NU: Single; A: Single; Scale: Boolean): TSCplx;

#NameTypeDescription
1NUSinglescalar
2ASinglescalar
3ScaleBoolean

Returns: TSCplx