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Owning Palette: Mathematics VIs

Use the Interp & Extrap VIs to perform 1D and 2D interpolation, piecewise interpolation, polynomial interpolation, and Fourier interpolation.

Palette Object	Description
Create Interpolating Polynomial	Takes the piecewise polynomial x locations and a 2D array of coefficients and forms the piecewise polynomial cluster for the Evaluate Interpolating Polynomial VI to use.
Create Mesh Grid (2D)	Takes two x domain and y domain arrays and forms X and Y 2D arrays, which are typically used to evaluate and plot functions of two variables. The data type you wire to the x domain input determines the polymorphic instance to use.
Evaluate Interpolating Polynomial	Takes the piecewise polynomial cluster and computes the interpolated values yi at each xi location.
Hermite Interpolation 1D	Performs one-dimensional interpolation using the cubic Hermite table-lookup interpolation method. This VI accepts tabulated X and Y values (independent and dependent variables, respectively) and provides interpolated values yi that correspond to each xi location. The VI looks up each value of xi in X and uses the relative location in X to find the interpolated value yi at the same relative location within Y.
Interpolate 1D Fourier	Performs interpolation by transforming the array X into the frequency domain, zero-padding and scaling appropriately for the interpolation factor you want and to maintain correct symmetry in the frequency domain, and then transforming back into the time domain to form the output interpolated array Y out.
Interpolate 1D	Performs one-dimensional interpolation using a selectable table-lookup method. This VI accepts tabulated dependent and independent variable values Y and X and provides interpolated values yi corresponding to each xi location. This VI finds each value of xi in X and uses the relative location in X to find the interpolated value yi at the same relative location in Y.
Interpolate 2D	Performs two-dimensional interpolation using a selectable table-lookup interpolation method when X, Y, xi, and yi are 2D arrays. You must manually select the polymorphic instance to use.
Polynomial Interpolation	Interpolates or extrapolates the function f at x given a set of n points (x[i]y[i]), where f(x[i]) = y[i], f is any function, and given a number x value.
Rational Interpolation	Interpolates or extrapolates f at x value using a rational function. The rational function passes through all the points formed by Y and X.
Search Ordered Table	Works on the assumption that ordered x array is in monotonically increasing or decreasing order and can therefore efficiently search for the relative index of the location of x value within the x array. The VI starts the search at the starting index and begins by using a fast hunting phase to roughly bracket the location and then narrows to the final bracket using a bisection search. The VI computes the fractional index location by using linear interpolation.
Spline Interpolant	Returns an array Interpolant of length n, which contains the second derivatives of the spline interpolating function g(x) at the tabulated points x[i], where i = 0, 1, …, n – 1.
Spline Interpolation 1D	Performs one-dimensional interpolation using the spline table-lookup interpolation method. This VI accepts tabulated X and Y values (independent and dependent variables, respectively) and provides interpolated values yi that correspond to each xi location. The VI looks up each value of xi in X and uses the relative location in X to find the interpolated value yi at the same relative location within Y.
Spline Interpolation	Returns a spline interpolated value at x value given the tabulated values (x[i], y[i]) and the second derivatives Interpolant that the VI obtains from the Spline Interpolant VI.