inter_data = F (a,b); Where x,z,y is measured data and inter_data,a,b are numbers. Basically i plotted streamlines for these two cases and now i want to see how much deviation is there between these streamlines (from case 1 to 2. See NearestNDInterpolator for more details. . These ordered grids of data can range from 1-D (for simple time. The Z values at these points are therefore nan, resulting in the surface point not being plotted. . hello everybody I wonder why Mathworks considers TriScatteredInterp(x,y,z) as an extrapolation function while it only interpolates inside the area defined by "x,y" scattered points and it doesn'. DT is a Delaunay triangulation of the scattered data locations, DT. X . Smooth was introduced in 2006, and smoothdata in 2017. This remains one key area I've not been able to find as good R equivalent. TriScatteredInterp must first calculate a Delaunay triangulation of the scattered points to use as a datagrid. F1=TriScatteredInterp(lon,lat,ssh, 'natural'); end. This should fix your problem without the need to change the function code. I know how to find CT # for any slice k corresponding to ith row and jth column, CT#=CT (i,j,k). X is a matrix of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside (ndim is 2 or 3). Since I've retired from consulting, not much incentive to spend $$ on. Having enough input (scattered) data points also helps. Version 1. 1. I want to use TRISCATTEREDINTERP for various y such that y=y/100, y=y/10, y=y*10 etc. Learn more about unexpected interpolation scatteredinterpolant triscatteredinterp bug? MATLABUsing TriScatteredInterp function in simulink. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. And now I'm able to evaluate value of F at any point. I have a 3D point cloud which isn't continuous. The matrix DT. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. Also the ref page for GRIDDATA now suggests you use a new class: "TriScatteredInterp is the recommended alternative to griddata as it is generally more efficient. The matrix is available here. Hello, I'm using TriscatteredInterp to interpolate 3D data. Cambiar a Navegación Principal. , TriScatteredInterp uses a Delaunay triangulation to determine this. 0. Learn more about volume, triscatteredinterp, 4d model I have a 4D model that I created of a nearby marsh that contains heavy metals. 0005 % 0006 % ZI = GRIDDATA(X,Y,Z,XI,YI) fits a surface of the form Z = F(X,Y) to the 0007 % data in the (usually) nonuniformly-spaced vectors (X,Y,Z). Can querying "TriScatteredInterp" be. I would like to average the data (about a small cell) at a every specific grid point (to lessen the scanner noise), instead of using matlab. 'natural', 'linear', and 'nearest'? I ask because my code is currently working fine with one of the three options (nearest) but the other two return a pattern of NaNs spaced regularly in otherwise healthy output data. All these points, we need to implement Delaunay triangles in C++. X is a matrix of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside (ndim is 2 or 3). If xi , yi are vectors then they are made into a 2-D mesh. Learn more about extrapolation, triscatteredinterp hello everybody I wonder why Mathworks considers TriScatteredInterp(x,y,z) as an extrapolation function while it only interpolates inside the area defined by "x,y" scattered points and it doesn'. Points that look close in one direction are in. That is easy. Then it evaluates the interpolant at different locations (val=F(x,y)). I have three vectors: x-coordinates, y-coordinates, topography values. . 1. To preserve the constraints save the DelaunayTri and recreate TriScatteredInterp after loading. Of course, if your company or university if current on maintenance, you can upgrade to the newest release for no additional cost. Use TriScatteredInterp instead. Bearbeiten: Vorschläge für die Verpackung: 1) TriScatteredInterp so umschreiben, dass es Modulos verwendet; 2) spiegeln Sie die Daten um die "Kanten" der Karte, interpolieren Sie und schneiden Sie sie dann auf die ursprüngliche Größe zurück; 3) Schauen Sie sich die Matlab Mapping Toolbox an, mit der Sie geografische Informationen. John on 13 Apr 2013. Learn more about scattered data, interpolation, triscatteredinterp Hi guys, I want to interpolate 2d scattered data from a CFD simulation to a regular grid using matlab's TriScatteredInterp. . The matrix DT. These are both in degrees. This non- monotonically increasing dataset means that I'll have to use triscatteredinterp, but I'm having issues wit. 然而，我似乎无法理解trisurf的工作原理（我尝试过使用它，但运气不佳）。. nan, rescale=False) #. interp3 problem. Learn more about meshgrid, triscatteredinterp, 3d plot, plot, gravity, topography, vectors Hi, I am trying to plot a 3D topography profile using gravity data. Learn more about triscatteredinterp fitting data non-monotonic dataHi, I was wondering if there was any way to texturemap multiple images onto specific portions of a surface. E. F = TriScatteredInterp(Q,V) creates an interpolant that fits a surface of the form V = F(Q) to the scattered data in (Q, V). Each point of my shape has a coordinate ( X,Y,Z) and also a measured parameter which indicates noise at that specific p. The column vector V defines the values at Q, where the length of V equals mpts. 0 (1. # I create "interpolazione. Show None Hide None. Yes, adjusting the step size could help produce a smoother result. vq = griddata(x,y,v,xq,yq) fits a surface of the form v = f(x,y) to the scattered data in the vectors (x,y,v). Learn more about triscatteredinterp, interpolation, error, column-vector, vector, column, formatI have two point clouds (XYZ coordinates) of different dimensions and would like to be able to calculate the difference between them (with the result as an XYZ array, with Z being the distance between them) and then plot both as surfaces together with the differences as a different color. {"payload":{"allShortcutsEnabled":false,"fileTree":{"fvcom_prepro":{"items":[{"name":"samples","path":"fvcom_prepro/samples","contentType":"directory"},{"name":"FVCOM. I can see this in the Activity mon. X is a matrix of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside (ndim is 2 or 3). Follow; Download. Smoothdata is a little more sophisticated, with more options, as you might expect, since it was introduced many years later. I temporarily mapped the p2p voltage data to the vertices of the surface closest to the point of measurement. DT is a Delaunay triangulation of the scattered data locations, DT. Image 1 - Plot of the imported data. Spatial coordinates for source and detector. So I did, and found to be twice slower for a 512 by 512 matrix. X. make an interpolant from the data: F = TriScatteredInterp (r,Z,sigma); make a grid of z and r points: [rgrid,Zgrid] = meshgrid (linspace (min (r),max (r)),linspace (min (Z),max (Z))); evaluate the interpolant (1) on the grid (2): sigmagrid = F (rgrid,Zgrid); use the gridded data to make a plot: contour (rgrid,Zgrid,sigmagrid) Plot Stress. DT is a Delaunay triangulation of the scattered data locations, DT. If you can post the mesh, I can post code that does the interpolation. I have three vectors: x,y (point coordinates) and v (fluid values). Learn more about triscatteredinterp, delaunaytri Hi, I have several routines where I create a TriScatteredInterp object from a DelaunayTri that has constraints on it. 1 value for each pair of x and y values. Use griddedInterpolant to perform interpolation. 31 KB) by Grazvydas. Learn more about interp2, triscatteredinterp, interpolation, table MATLAB Hi, I have a table with density values dependent on pressure and temperature, rho(p,T), and I want to be able to interpolate between them. random. I am not volunteering to actually do these calculations by hand, but the slowness of TriScatteredInterp makes me think it's doing a lot more work than it needs to do. X. It won't work to fit a point cloud like you have. Then I use the expanded data to interpolate the grid located in [0, 2π]. de 2011. Now I understand how TriScatteredInterp works in Matlab. X . . There are a few gaps in it. So that proves concept. Replace the zeros with NaN elements, then throw it into inpaint_nans. In MATLAB you can use either the function griddata or the TriScatteredInterp class (Note: as of R2013a scatteredInterpolant is the recommended alternative). The interpolation points are all (xi, yi). This produces a surface of the form V = F(X). file = 'OMI-Aura_L2-OMNO2_2015m1231t0651-o60959_v003-2018m0617t014246. . I have three vectors: x,y (point coordinates) and v (fluid values). These are "flat" surfaces that use color to show the power from each data point. Any of these arithmetic operations will produce a NaN: zero/zero, zero*infinity, infinity/infinity, infinity-infinity. Link. The idea being that I will create the probable signal strengths for the various locations and get some sort of super delaunay triangulation. So I would like to plot/construct a "volumetric mesh" for multiple range bins. I'm using TriScatteredInterp for 3 dimensional interpolation. I have three vectors: x,y (point coordinates) and v (fluid values). Use your ix variable to do it on the specified columns: That will make X a list of the rows that have not been extracted. Learn more about triscatteredinterp, griddedinterpolant, efficient interpolation . Warning: Creating a TriScatteredInterp using a constrained DelaunayTri. TriScatteredInterp は、2 次元または 3 次元空間にある散布したデータ セットに対して内挿を実行するために使用します。 散布データの集合は、X の位置で定義されるため、対応する値 V は、X の Delaunay 三角形分割を使って計算することができます。 これは、V = F(X) という形式の表面を生成します。F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. If you need to not disturb the original, make a copy. Learn more about extrapolation, triscatteredinterp . We have x,y,z points for N X 3 dimensions. Learn more about triscatteredinterp, interpolation, regular, grid, reg, change, values Hello, I am currently using Triscatteredinterp to transform a regular grid (659 x 3600 x 1682) to this grid (659 x 3127 x 254). Now consider the simple test code. DT is a Delaunay triangulation of the scattered data locations, DT. Plotting the surface corresponding to the interpolated data on the grid. As a simple test, say the data has the following format (i. ERROR: Input data must be specified in. In this case, you may want to try TriScatteredInterp, somewhat like this. This is based, in part, on the proximity of the points. You might have been confused because of the [X, Y] argument confusion in TriScatteredInterp. So I've used function F=TriScatteredInterp (x,y,z,'method') to create the interpolant F. Your data has huge expanses between those ovals where no information is provided, but a triangulation MUST span the holes. Learn more about lion os, 2010a, triscatteredinterp, x11, crash Matlab 2010a (64 bit), does run on Lion OS, however there is a serious problem when trying to run a "TriscatteredInterp" command. Learn more about triscatteredinterp fitting data non-monotonic data I have data that is acquired over several hours at non-standard sampling rates. R2012b has brung my machine to about all it can do even after adding all the memory it can hold. Inicie sesión cuenta de MathWorks; Mi Cuenta; Mi perfil de la comunidad; Asociar Licencia; Cerrar sesiónDescription. Triscatteredinterp outputs an interpolant F that will provide the value of the function at some location (x) in 2D or (x,y) in 3D. scatteredInterpolant returns the interpolant F for the given data set. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. Learn more about scattered data, interpolation, triscatteredinterp Hi guys, I want to interpolate 2d scattered data from a CFD simulation to a regular grid using matlab's TriScatteredInterp. I'm wondering if anyone else has had problems using constrained 2D Delaunay triangulations to create TriScatteredInterp objects, and if anyone has a suggested work-around. I have three vectors: x,y (point coordinates) and v (fluid values). The data is already gridded on a regular grid. % X, Y,Z は元のベクト. The interpolation points are all (xi, yi). Interpolating points of a 3D point cloud. I tested both TriscatteredInterp, and scatteredInterpolant on a large set of data, interpolating 1e7 points through a random surface compiosed of 10000 points in 2-dimensions. Cambiar a Navegación Principal. # I create "interpolazione. X. X . p(2,:)), mesh, x, y); Use scatteredInterpolant to perform interpolation on a 2-D or 3-D data set of scattered data . A good tool for that job is the TriScatteredInterp class. One-dimensional interpolation. . Then do Barycentric interpolation in a triangle as shown in. 0. Hi, im wondering why querying the TriScatteredInterpolant is so much slower and so much more size dependent than griddedInterpolant. Answers (1) For interp3 to work, the data must be in a grid. The inputs x, y, z are either vectors of the same length, or. Historically, the MATLAB approach was to use qhull to produce a triangulation, and then for each query point, query which triangle it was in and use the vertices of the triangle to do the interpolation. Generate a regular mesh from irregular data using interpolation. This remains one key area I've not been able to find as good R equivalent. Learn more about triscatteredinterp, griddedinterpolant, efficient interpolation . X is a matrix of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside (ndim is 2 or 3). I would like to translate *TriScatteredInterp* from *Matlab to C#* and I do these operations but they don’t work. . inpaint_nans will also work here. The column vector V defines the values at X, where the length of V. The problem is the power is only interpolated using data from a single range bin, and nothing above or below. Adding to Ben's answer, you can use the view command. Learn more about triscatteredinterp, interpolation, error, column-vector, vector, column, formatF = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. The scatteredInterpolant class supports scattered data. These are "flat" surfaces that use color to show the power from each data point. Here is an example: import matplotlib. class scipy. According to the MATLAB documentation, applying the TriScatteredInterp function on a scattered dataset with duplicates will implicitly remove the duplicates and average the associated data values. Learn more about triscatteredinterp, interpolation, 3d, lines, surface MATLAB I am trying to compute a surface from 3 lines using interpolation and not getting the expected results. open (file); % Optain information about the file. X is of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3. I tried to interpolate a set of radar reflectivity values using TriScatteredInterp (and later with scatteredInterpolant). the function is known. TriScatteredInterp is good for fitting 2D surfaces of the form z = f(x,y), where f is a single-valued function. × License. random. 01) xi,yi = np. X. These are "flat" surfaces that use color to show the power from each data point. TriScatteredInterp is used to perform interpolation on a scattered dataset that resides in 2-D or 3-D space. X is of size mpts -by- ndim , where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3 . The example below plots a saddle. So I did, and found to be twice slower for a 512 by 512 matrix. 这种方法. X is of size mpts -by- ndim , where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3 . Trimomatic中提供两种质量过滤方式，这两种情况中一般都是会根据碱基质量值保留5'端的数据，而剪切掉3’端的数据，这是符合Illumina的测序情况的，因为在Illumina中一般都会是3'端的数据质量较差，接下来看两种不同的方法：. inter_data = F (a,b); Where x,z,y is measured data and inter_data,a,b are numbers. If you need to not disturb the original, make a copy. x = randn(100,1); y = randn(100,1); get_solution_at_xy(sin(pi*mesh. You can also set the 'method' property of the TriScatteredInterp object to 'natural' to get a smoother result, as well, at the expense of longer computation time. X . The surface can be evaluated at any query location QX, using QV =. So you end up with long, thin triangles, which are abominations when doing interpolation. The values along its columns are constant. Unexpected interpolation result when using. I noticed that my computer is using only one core out 4 (my machine is a MacbookPro, Intel 2720qm). Learn more about contour, contourf, mesh, meshgrid, griddata, triscatteredinterp MATLAB I've imported data into Matlab from a thermal Finite Difference which simulates the temperature profile produced on the surface of a metal plate during electron beam welding. e. This means that my input data might be 3D, but I can't call the interpolant F as F(input1, input2, input3) because I don't know whether it is 3D. Gnu Octave, Get every nth row of a matrix/vector: Now, remove rows from the original matrix which will give you a list of the rows not extracted. Then, for all your desired grid points x', y', please search the triangle in which your x',y' is located. Unfortunately I don't know what you should use for that situation, so maybe someone else will chime in here. . Type "doc contour" into MATLAB for details. All these points, we need to implement Delaunay triangles in C++. TriScatteredInterp は、2 次元または 3 次元空間にある散布したデータ セットに対して内挿を実行するために使用します。 散布データの集合は、X の位置で定義されるため、対応する値 V は、X の Delaunay 三角形分割を使って計算することができます。 F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. . × License. Is there a way to have the fast performance of the griddedinter. It finds values of a two-dimensional function underlying the data at intermediate points. Learn more about unexpected interpolation scatteredinterpolant triscatteredinterp bug? MATLABERROR: Input data must be specified in. Use the new scatteredInterpolant class instead. TriScatteredInterp doesn't extrapolate. So you end up with long, thin triangles, which are abominations when doing interpolation. See the help and documentation for the. zi = interp2 (x, y, z, xi, yi) zi = interp2 (z, xi, yi)I need to have a scatter plot (r,theta,Z) where Z values are represented with a colorbar. linear tessellate the. I tried to use "TriScatteredInterp"; however I received this error: "Z must be a matrix, not a scalar or vector. On Thu, Sep 14, 2017 at 5:58 AM, Lester Anderson <address@hidden> wrote: Hello, I have come across a bit of code I am trying to get to run in Octave, but found the function TriScatteredInterp:Learn more about interp2, triscatteredinterp, interpolation, table MATLAB Hi, I have a table with density values dependent on pressure and temperature, rho(p,T), and I want to be able to interpolate between them. I have one more case of u2, v2, w2, each one of size NxNxN. TriScatteredInterp from 3 lines to get surface. As my initial data had quite a few NaN. hello everybody I wonder why Mathworks considers TriScatteredInterp(x,y,z) as an extrapolation function while it only interpolates inside the area defined by "x,y" scattered points and it doesn'. 289. 我还看. Learn more about interpolate, triscatteredinterp, for loop, latitude, longitude I am currently having a problem interpolating unevenly spaced grid data. scatteredInterpolant returns the interpolant F for the given data set. Description. Why is scatteredInterpolant slower than. The matrix DT. X is of size mpts -by- ndim , where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3 . Interpolating or resampling algorithm in matlab for transformed 3D image, preferably sinc interpolation. . X is of size mpts -by- ndim , where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3 . The griddata function interpolates the surface at the query points specified by (xq,yq) and returns the interpolated values, vq. Hello, I'm using TriscatteredInterp to interpolate 3D data. This produces a surface of the form V = F(X). Thank you very much for your help! clear. if got a three vectors of scattered x, y and z data. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. . g. Z = F(X, Y); % Evaluates this interpolant at every lattice point. DT is a Delaunay triangulation of the scattered data locations, DT. Here's how. xls',1); xd2=xlsread('3dcr. 1. Learn more about triscatteredinterp, scatteredinterpolant I tried to interpolate a set of radar reflectivity values using TriScatteredInterp (and later with scatteredInterpolant). Learn more about triscatteredinterp . interpolate. Then, find the gradient of z by specifying the spacing between points. The interpolation points are specified by xi, yi, zi . . Learn more about triscatteredinterp, griddedinterpolant, efficient interpolation . . Use them to calculate z. F = TriScatteredInterp(DT,V) uses the specified DelaunayTri object DT as a basis for computing the interpolant. TriScatteredInterp is good for fitting 2D surfaces of the form z = f(x,y), where f is a single-valued function. I tried to fix this by wrapping the data as follows. So I've used function F=TriScatteredInterp(x,y,z,'method') to create the interpola. In the image you can see an example of graph obtained. 一、 实验要求. Apr 11, 2014 at 9:18. 1. Use the contour () function. 2、熟练掌握函数polyfit进行曲线拟合、nlinfit进行指定函数的拟合，并且会进行案例分析。. There is a hypothesis that the period is 2π. e. " I want to know how interpolate the scattered data over the non- uniform grid ( for the trapezoid region) % X coordinate of scatered data. TriScatteredInterp is used to perform interpolation on a scattered dataset that resides in 2-D or 3-D space. pyplot as plt import numpy as np from scipy. TriScatteredInterp from 3 lines to get surface. What I have is a matrix of x, y, z points that is my base data. X is of size mpts-by-ndim, where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3. scatteredInterpolant returns the interpolant F for the given data set. Answers (1) These are very similar codes, doing similar things. So I did, and found to be twice slower for a 512 by 512 matrix. Specifically, the 'scatteredInterpolant' function defaults to the extrapolation method of 'linear' when the interpolation method is 'linear' or 'natural' and the extrapolation method of 'nearest. Point 1 : (x1, y1,. Learn more about triscatteredinterp . ERROR: Input data must be specified in. There is no use of multiple cores, even today, using R2022b. % aerofoilcoord = getBladeGeometry (R,chords,aerofoils) % Interpolate between the aerofoils then apply the chord scaling to each. If not: Theme. Learn more about extrapolation, triscatteredinterp hello everybody I wonder why Mathworks considers TriScatteredInterp(x,y,z) as an extrapolation function while it only interpolates inside the area defined by "x,y" scattered points and it doesn'. Accepted Answer. I have a data file containing 2 columns of x and y axis values. 01,0. Sorted by: 1. For 3-D interpolation, the inputs x, y, and z define the points where the function v = f (x, y, z) is evaluated. %# insert the code from @Alexandrew answer to generate meshgrid [XI, YI] = meshgrid (xi, yi); TSI = TriScatteredInterp (x,y,z); ZI = TSI (XI,YI);. One-dimensional interpolation. You can use TriScatteredInterp to interpolate your data onto a regular grid, which you then can use to plot the surface using surf, or a heatmap using contourf. qhull is a third-party library; if I recall correctly it is from a UK university. In MATLAB you can use either the function griddata or the TriScatteredInterp class (Note: as of R2013a scatteredInterpolant is the recommended alternative). The matrix DT. DT is a Delaunay triangulation of the scattered data locations, DT. F = TriScatteredInterp(X, V) creates an interpolant that fits a surface of the form V = F(X) to the scattered data in (X, V). The 'TriScatteredInterp' function does not perform any extrapolation, whereas the 'scatteredInterpolant' function performs extrapolation by default. The column vector V defines the values at X, where the length of V. Now consider the simple test code. Updated 27 Nov 2012. If the original grid of points is regular, then interp3 () should be fine. Learn more about scattered data, interpolation, triscatteredinterp Hi guys, I want to interpolate 2d scattered data from a CFD simulation to a regular grid using matlab's TriScatteredInterp. F = TriScatteredInterp(X, V) creates an interpolant that fits a surface of the form V = F(X) to the scattered data in (X, V). Overview; Functions. The interp2 command interpolates between data points. bin','w'); fwrite (fid,vq,'single'); fclose (fid); In the above code a, b and c are the x, y and z coordinates of each point and d is the corresponding intensity values for the desired range. Learn more about triscatteredinterp, interpolation, error, column-vector, vector, column, formatCan anyone direct me to detailed information regarding the interpolation options available to TriScatteredInterp, i. The matrix DT. Historically, the MATLAB approach was to use qhull to produce a triangulation, and then for each query point, query which triangle it was in and use the vertices of the triangle to do the interpolation. According to the MATLAB documentation, applying the TriScatteredInterp function on a scattered dataset with duplicates will implicitly remove the duplicates and average the associated data values. Griddata3 and TriScatteredInterp will not interpolate data outside of the convex hull of the data. 案例二：. Ingénieur indépendant en mécatronique - Conseil, conception et formation. X is of size mpts -by- ndim , where mpts is the number of points and ndim is the dimension of the space where the points reside, 2 <= ndim <= 3 . And this happens even if I'm using linear interpolation on double numbers in the cartesian to sperical conversion and using nearest neighbour in TriScatteredInterp. I want to employ F = TriScatteredI. 以下の例では、最近傍法の内挿を用いて面を作成します。. Accepted Answer. The scatteredInterpolant class performs interpolation on 2-D and 3-D scattered data with support for extrapolation outside the convex hull of the sample points. As my initial data had quite a few NaN values, the final interpolation inco. X is a matrix where each row is a copy of x, and Y is a matrix where each column is a copy of y. % aerofoilcoord = the coordinates defining the blade geometry. One of nearest return the value at the data point closest to the point of interpolation. 1 Comment. So I would like to plot/construct a "volumetric mesh" for multiple range bins. I notice that the interpolated results are different. . New in version 0. Use *TriScatteredInterp* instead. I've successfully used TriScatteredInterp to interpolate scattered nodal data onto the output of meshgrid/ndgrid, but the operation is time consuming (I start with about 52 thousand nodes, and that's just. TriScatteredInterp was the predecessor to scatteredInterpolant and griddata the predecessor to TriScatteredInterp. I am looking for data at xi,yi,zi. The matrix DT. The Voronoi diagram of a discrete set of points X decomposes the space around each point X(i) into a region of influence R{i}. The variables have dimensions 151x156x39. Since you're dealing with a cylinder, which is, in essence, a 2D surface, you can still use TriScatterdInterp if you convert to polar coordinates, and, say, fit radius as a function of. using TriScatteredInterp with a Image.