Interpolation.interp2 Method (InArray<complex>, Nullable<complex>, InArray<Double>, InArray<Double>, InArray<Double>, InArray<Double>, Int32, InterpolationMethod)

public static RetArray<complex> interp2(
	InArray<complex> V,
	Nullable<complex> outOfRangeValues,
	InArray<double> X1 = null,
	InArray<double> X2 = null,
	InArray<double> Xn1 = null,
	InArray<double> Xn2 = null,
	int k = 0,
	InterpolationMethod method = InterpolationMethod.linear
)

Public Shared Function interp2 ( 
	V As InArray(Of complex),
	outOfRangeValues As Nullable(Of complex),
	Optional X1 As InArray(Of Double) = Nothing,
	Optional X2 As InArray(Of Double) = Nothing,
	Optional Xn1 As InArray(Of Double) = Nothing,
	Optional Xn2 As InArray(Of Double) = Nothing,
	Optional k As Integer = 0,
	Optional method As InterpolationMethod = InterpolationMethod.linear
) As RetArray(Of complex)

Dim V As InArray(Of complex)
Dim outOfRangeValues As Nullable(Of complex)
Dim X1 As InArray(Of Double)
Dim X2 As InArray(Of Double)
Dim Xn1 As InArray(Of Double)
Dim Xn2 As InArray(Of Double)
Dim k As Integer
Dim method As InterpolationMethod
Dim returnValue As RetArray(Of complex)

returnValue = Interpolation.interp2(V, outOfRangeValues, 
	X1, X2, Xn1, Xn2, k, method)

Parameters

V

Type: ILNumerics.InArray<complex>
Matrix with sample values defined in meshgrid format.

outOfRangeValues

Type: System.Nullable<complex>
Scalar value used to mark values whose position lays outside the range defined by X1 and X2. Null: extrapolate.

X1 (Optional)

Type: ILNumerics.InArray<Double>
[Optional] Positions of grid points along the rows of V, specified as a matrix in meshgrid format or grid vector. Monotonically increasing along the rows.

X2 (Optional)

Type: ILNumerics.InArray<Double>
[Optional] Positions of grid points along the columns of V, specified as a matrix in meshgrid format or grid vector. Monotonically increasing along the columns.

Xn1 (Optional)

Type: ILNumerics.InArray<Double>
[Optional] Query point positions for dimension 1 (rows), specified as grid vector or matrix in meshgrid format. Monotonically increasing.

Xn2 (Optional)

Type: ILNumerics.InArray<Double>
[Optional] Query point positions for dimension 2 (columns), specified as grid vector or matrix in meshgrid format. Monotonically increasing.

k (Optional)

Type: System.Int32
[Optional] Refinement factor for default query grid positions. Ranges specified by X1 and/or X2 are split k times. Ignored for Xn1 or Xn2 being not null respectively. Default: 1.

method (Optional)

Type: ILNumerics.Toolboxes.InterpolationMethod
[Optional] Interpolation method. Default: linear.

Return Value

interp2(InArray<complex> , Nullable<complex> , InArray<Double> , InArray<Double> , InArray<Double> , InArray<Double> , Int32, InterpolationMethod) performs two dimensional interpolation over the given data matrix V defined in meshgrid(InArray<complex> , InArray<complex> , InArray<complex> , OutArray<complex> , OutArray<complex> ) format. The parameter X1 specifies the positions of the grid points in V along the first dimension (along the rows of V). X2 determines the positions along the 2nd dimension (along the columns of V). Hence, V forms a regular, rectilinear grid of (non-)uniform spacing. Note the order of the dimensions in V: as determined by the meshgrid function the first dimension is considered to correspond to the rows instead of the columns. This order is useful for visualization purposes and plotting, where the X axis is commonly expected along the rows. Use interpn(InArray<complex> , Nullable<complex> , InCell, InCell, InterpolationMethod) as an alternative.

Values in X1 and X2, if provided, must be strictly monotonically increasing but not necessarily be uniform. If any of X1 and/or X2 are ommitted, default grid positions are assumed with uniform range of spacing 1: 0:n x 0:m, where [m+1,n+1] = size(V).

Values in Xn1 and Xn2, if provided, must be strictly monotonically increasing but not necessarily uniform. If any of Xn1 and/or Xn2 are ommitted, default query grid positions are assumed by subdividing X1 and/or X2 respectively, 'k' times.

Interpolation methods: all methods from the enum InterpolationMethod are supported. See [!:interp1(InArray<complex>, complex?, InArray<complex>, InArray<complex>, int, InterpolationMethod)] for a detailed description.

[ILNumerics Interpolation Toolbox]

//generate any meshgrid
Array<complex> X2 = 1;
Array<complex> X1 = meshgrid(linspace<complex>(-2, 2, 20), linspace<complex>(-2, 2, 20), X2);
Array<complex> V = X1 * exp(-(X1 * X1 + X2 * X2));

//define query meshgrid
Array<complex> Xn2 = 1;
Array<complex> Xn1 = meshgrid(linspace<complex>(-3, 3, 50), linspace<complex>(-3, 3, 50), Xn2);

//Interpolate
Array<complex> Vq = Interpolation.interp2(V, X1, X2, Xn1, Xn2, method:InterpolationMethod.spline, outOfRangeValues: complex.NaN);

//or spline interpolate using refinement factor
Array<complex> Vq = Interpolation.interp2(V, X1, X2, k:2, method:InterpolationMethod.spline);

//or nearest neighbor interpolation of a meshgrid with only one Xn2 specified.
Array<complex> Vq = Interpolation.interp2(V, X1, X2, Xn2:Xn2, method:InterpolationMethod.nearest);

//or linear interpolate a meshgrid
Array<complex> Vq = Interpolation.interp2(V);

Reference