If the projectile hits the barrier, the projectile path should stop at that point. 2, No. The corresponding Matlab code is. T を指定すると、 PQ. Syntax. I have a matrix A made up of several 2D points. In the function thatimplementation of direct computing of surface curvatures for point-set surfaces - CurvatureEstimation/nearestneighbour. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. 5377, 1. bmp","path":"ANTS1_intro/amsterdam. the topographies look very good and dipolar. They. Could really use some help converting the last line of the Matlab code above to Julia!Alternate search functions to speed up code. I have tried profiling my code and apparently it is very slow to the use of the desarchn algorithm. collapse all. Using this function might be another option to compute the point of a regular grid that is nearest to a given sample and return the indices. 5 output for a given location and. The documentation for this function is here: dsearchnThis MATLAB function returns the indices of the closet scored in P to an query points in PQ measured with Geometrician length. XI is a p -by- n matrix, representing p points in N-dimensional space. Nearest 2-D Points. Two things in the Fortran code should be corrected to get the results to match between the Python and Fortran versions. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-Simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. Share. If outval is [], then k is the same as in the case k = dsearchn(X,T,XI). Nikhil Kori on 7 Jul 2020. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. In this code I calculate the modal shapes using the Ritx method, and then apply an equation to get the modal force and then sum over the different modes and. Then given an arbitrary point (x1, y1), we can find the appropriate grid cell by finding the closest x to x1 and the closest y to y1. This class provides an index into a set of k-dimensional points which can be used to rapidly look up the nearest neighbors of any point. In the 4-D example, you can compute the distances, dnn, as follows: [xi,dnn] = dsearchn(X,tri,q); Point-Location Search. generate a random point, i. If outval is [], then k is the same as in the case k = dsearchn(X,T,XI). nearestIndex is the indices into vertices nearest to points nearestValues is the coordinates for nearestIndex This function is just a wrapper for dsearchn. Installation. cKDTree vs dsearchn. find the closest vertex from the existing list. this is my project for projectile motion we done everything and its working we're. Making for every point in B a list of nearest points from A. Most of the projects developed for Matlab run on Octave too. ; Related topics[k,dist] = dsearchn(PQ,P) k = 8 dist = 0. shape[0]): distances = np. 3 Answers. This documnentation and the algorithm section of it might be usefull for you Nearest point search. Quantization aware training is a method that can help recover accuracy lost due to quantizing a network to use 8-bit scaled integer weights and biases. I am unsure how to accomplish this with k = dsearchn (P,PQ) or Idx = knnsearch (X,Y,Name,Value). Using this function might be another option to compute the point of a regular grid that is nearest to a given sample and return the indices. Otherwise, move to the right subtree. 8 Yo( : , j ) = dsearchn ( Screen Sampling , Yo(: , j ) ) ; %find the s p a t i a l pixel index on screen 9 Vo( : , j ) = convertViewIndex (Vo(: , j ) , Angular Res ) ;%find the angular view index on screen 10end With the above function giving the transported screen side light field, the following code counts the samples andmatlab tutorial linear discriminant via generalized eigendecomposition - eeg_gedlda_tutorial/filterFGx. Answer a few questions to help the MATLAB community. Theme. Issue. The adaptive coupling PD-FEM model is presented as the third method to solve crack growth in the notched plate. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. At the moment, I am just doing: Theme. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. K = dsearch (x,y,TRI,xi,yi) returns the index into x and y of the nearest point to the point ( xi, yi ). I have a test set that is 10000 points and of course same number of pixels. Description. We have compiled a list of solutions that reviewers voted as the best overall alternatives and competitors to MATLAB, including Fusion, RapidMiner, SOLIDWORKS, and Alteryx. If outval is supplied, then the values of xi that are not contained within one of the simplices tri are set to outval . . To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. Add Hungarian translation for project description files. The best MATLAB alternative is GNU Octave, which is both free and Open Source. k = dsearchn (A,0. % need a baseline file, so everything is placed in. ; hgsave. % Scalar Quantizer codebook generator for Codec 2 % % Wojciech Kaczmarski, SP5WWP % M17 Project, 28/01/2022 %-----% %constsHelp selecting a search algorithm, dsearchn,. My que. This code uses a for loop in conjunction with the range () function to generate a sequence of numbers starting from 0, up to (but not including) 10, and with a step size of 2. dsearchn() Command is slowing down my algorithm,. Mex and qhull are used because they're fast! Why do you need to know this computational complexity?Hi everyone! I wanted to generate C code from Matlab code. A value between 1,000 and 100,000 is. Syntax. png) in Matlab. The documentation for this function is here: dsearchn class scipy. fid = fopen (filename); lines = textscan (fid,'%s','delimiter',' '); fclose (fid); lines = lines {1};Accepted Answer: KSSV. The motor constant calculated was approximately 8. Output: To delete a node in a binary search tree, we need to search it. The function pauses before each step in the algorithm, so you can slowly step. 7]; [k,dist] = dsearchn. Hi. Find matrix (meshgrid) indices near plotted vector (points) I am attempting to grab several datapoints that are near a vector of points (represented by a line in the plot). e, a "vertex". class scipy. For instance, given a data frame, you should extract the row indices that match your criteria. For a 1e5 x 1e5 matrix all cores are used (most likely). KDTree (X, leaf_size = 40, metric = 'minkowski', ** kwargs) ¶. See also: dsearchn, tsearch. 6, 2011 13 | P a g e Assessing 3-D Uncertain System Stability by UsingIntroduction. The results are based on a previously proposed method for localizing a point with respect to a convex hull boundary,. See Spatial Searching for more information on triangulation-based search. The documentation for this function is here: dsearchn1. The problem is, given a starting point and limited boundre, how. [k,dist] = dsearchn(___) also returns the distance from each point in P to the corresponding query point in PQ. This way it handles multiple occurrences of one of the numbers, and returns the result in the correct order: [tf,loc] = ismember (a,b); tf = find (tf); [~,idx] = unique (loc (tf), 'first'); c = tf (idx); The result: >> c c = 3 6 5. They can give the same or different results, so it's a subtle distinction! 2 Answers. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. Provides an example of solving an optimization problem using pattern search. Answers (1) Sean de Wolski on 25 Jan 2012. The documentation for this function is here: dsearchncreate a mesh. k = dsearchn(P,T,PQ) 通过使用 Delaunay 三角剖分 T 返回 P 中最近点的索引，其中 T = delaunayn(P)。 当 PQ 包含大量点时，提供 T 可以提高搜索性能。 k = dsearchn( P , T , PQ , outind ) 返回 P 中最近点的索引，但对 P 的凸包之外的查询点赋给索引值 outind 。How to Repair Dsearchn. I'm working with MNIST data set 60000 points each of 784 pixels. IDX文件格式. Contribute to vishrawji/GED-tutorial development by creating an account on GitHub. This is something I want to avoid. 5]. 021 should be selected as it is the nearest value to the range. 1 1. An official Windows binary installer is also available. The sizes in each dimension are 4-byte. See also: dsearchn, tsearch. Respuesta aceptada: KSSV. k = dsearchn(X,T,XI,outval) returns the indices k of the closest points in X for each point in XI, unless a point is outside the convex hull. Description. greater than 2-D) arrays using the function FIND, it is best to get a single linear index from FIND then convert it to subscripts using the function IND2SUB. 1;0. collapse everything int web. Math functions provide a range of numerical computation methods for analyzing data, developing algorithms, and creating models. This will work even if installing the C and Cython extensions fails, using pure-Python fallbacks. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. dsearchn returns the indices of the closest points in P to the query points in PQ measured in Euclidean distance. : idx = dsearchn (x, tri, xi) ¶: idx = dsearchn (x, tri, xi, outval) ¶: idx = dsearchn (x, xi) ¶: [idx, d] = dsearchn (…) ¶ Return the index idx of the closest point in x to the elements xi. If compatibility with SciPy < 1. Running the Sample. If XI(J,:) is outside the convex hull, then K(J) is assigned outval, a scalar double. Inf is often used for outval. Hi, I am struggling with the sourceanalysis of EEG data which was recorded with Biosemi 128 electrodes. k = dsearchn(P,T,PQ) returns the indices of the closest points in P by using the Delaunay triangulation T, where T = delaunayn(P). I'm trying to figure out what is the most efficient way in Matlab (besides just using built-in fit functions) to determine KNN for K=1 over this test set. argsort (a [, axis, kind, order]) Returns the indices that would sort an array. . KDTree¶ class sklearn. Hi guys! I'm trying to build a tool to let me extract data from other figures (Sadly from . idx = dsearchn (x, tri, xi) : idx = dsearchn (x, tri, xi, outval) : idx = dsearchn (x, xi) : [idx, d] = dsearchn (…) Return the index idx of the closest point in x to the elements xi . Alternate search functions to speed up code. Use dsearchn again with my (x,y) grid and the remaining curve from the previous step as inputs to find the grid points that are closest to the remaining curve; However, this approach has 2 problems: dsearchn does not take into account uniqueness of points: some of curve points map onto the same grid point. 之前：. . Linear interpolation of n-dimensional scattered dataThis file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. I have a matrix A made up of several 2D points. zeroIX=dsearchn (mydata,0); However, this only gives me the very first value. . Basically they are from the next frame of a movie. dsearchn relies on mex and qhull to do most of the work. I am trying to project scattered 2D raw data (rawX, rawY, rawZ) onto a 2D grid (intX, intY) using GRIDDATA() The scattered 2D raw data has a data gap where no measurements have been made (rawZ = 0), as shown in the figureThe function finds just one of the nearest vertices in the cloud for each of these points. 7]; [k,dist] = dsearchn (P,PQ); Plot the data points and query points, and highlight the data point nearest to each query point. Learn more about TeamsIn your example, you are returning A, rather than the closest point in B. Answers (1) Nikhil Kori on 7 Jul 2020. In this case, it should be 0. If you want the numeric values: Theme. In patternsearch, a search is an algorithm that runs before a poll. Respuesta aceptada: KSSV. 在 CPU 和/或 GPU 上并行执行 MATLAB ® 程序和 Simulink ® 仿真. tr. If I understand correctly, that is what the "signed distance field" describe, i. If outval is supplied, then the values of xi that are not contained within one of the simplices tri are set to outval. I would like to find the points in B that are closest to each point in A. Add a comment | Your Answer Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Click Submit. It also returns the distances and the outside index value for query points outside of the convex hull. function fi = tinterp ( p, t, f, pi, i ) %*****80 % %% tinterp(): Triangle based linear interpolation. I have updated it now to use DSEARCHN so it works again. bmp","contentType":"file"},{"name. Document fsolve output “info” -2 . kd-tree for quick nearest-neighbor lookup. noticed that the dsearchn function includes an optional output 'd' to return the distance to the nearest triangulation point , but it is not described at all in the docstring. rng default ; P = rand ( [10 2]); PQ = [0. It can be used with or without a Delaunay triangulation T, where T is a matrix of the Delaunay. 125k 15 15 gold badges 256 256 silver badges 359 359 bronze badges. Introduction. Shows how to write an objective function including extra parameters or vectorization. That's easily done in cartesian coordinates so I temporarily converted the (lon,lat) coordinate to equidistant. zip","path":"AnalyzingNeuralTimeSeriesData. search: [verb] to look into or over carefully or thoroughly in an effort to find or discover something: such as. XI is a p-by-n matrix, representing p points in. m at master · Tonsty/CurvatureEstimationI have a code which tracks a series of footballs in a video. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. k int or Sequence[int], optional. If I have for example a vector like this:Result = Data(dsearchn(Data(:,1), Distance2), 2); Altitude = -cumtrapz(Distance2, Result)/1000; Distance 1 and Distance 2 has different size with same values so I am comparing them to get corresponding value of Gradient to use with Distance 2. I have already stored the required points in a separate array and used both 'desearchn' and 'rangesearch' and 'knnsearch' matlab methods. dsearch requires a triangulation TRI of the points x, y obtained using delaunay. The result is a vector of node IDs in order of their discovery. md","contentType":"file"},{"name":"RESS_example_script. . 8 0. If I have for example a vector like this:[k,dist] = dsearchn(___) also returns the distance from each point in P to the corresponding query point in PQ. However, you should be able accomplish what you need just by using the base and stats packages. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. Function Reference: dsearchn. spatial. t = tsearchn(X,TRI,XI) returns the indices t of the enclosing simplex of the Delaunay triangulation TRI for each point in XI. A short example: dsearchn: N-D nearest point search. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. A method of approximately equivalent efficiency is probably scipy's KDTree or better yet cKDTree:. : idx = dsearchn (x, tri, xi) ¶: idx = dsearchn (x, tri, xi, outval) ¶: idx = dsearchn (x, xi) ¶: [idx, d] = dsearchn (…) ¶ Return the index idx of the closest point in x to the elements xi. I don't think you need a baseline. Using this function might be another option to compute the point of a regular grid that is nearest to a given sample and return the indices. 81, which is also close to the. k = dsearchn (A,0. Copy. The applied load is a thermal load (temperure ) solved by Ansys Fluent and exported in the from of csv format. Wrap your search query in double quotes. It labels comments and numbers fine, but no commands. Link. 使用 MATLAB 的并行计算通过桌面、集群和云中的 CPU 和 GPU 提供帮助您利用更多硬件资源的语言及工具。. Nearest 2-D Points. Ideally, the indices of the datapoints very close to the line's datapoints will be pulled and I can reference them later for some. Nearest 2-D Points. 1 0. Using this function might be another option to compute the point of a regular grid that is nearest to a given sample and return the indices. Learn more about string, search, index, dsearchn, find I have two cell arrays, one is the array I want to find indices of multiple strings. Once the leaf node is reached, insert X to its right or left based on the. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. The order of folders on the search path is important. ) See also the requirements for the HDF5 module, used for "v7. 5; 0. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. jpg) using signed distance. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. 87 -0. Share. If outval is supplied, then the values of xi that are not contained within one of the simplices tri are set to outval. example. m , the. See examples of SEARCH used in a sentence. Like stated in the comments you need to define what you want to happen if your "choice" of time (1st column of data) is not contained in your matrix. Click Dislike. Function Reference: dsearchn. But in this case for example, I need the index of the middle one. % 2. Using this function might be another option to compute the point of a regular grid that is nearest to a given sample and return the indices. 我们十分激动地宣布，我们为DeepL API开发的Python客户端库已经发布。. – user3275421. EW = DomainWidth / ENPR; % The width of each finite. The type and value of the latitude depends on the way you define the line. Copy. Get MATLAB duty returns the indices of the immediate matters the P up the query items in PQ measured in Euclidean distance. Nearest 2-D Points. example. Hey all, I have a simple vector containing my data and wanna find the index of its value closest to zero. Find matrix (meshgrid) indices near plotted vector (points) I am attempting to grab several datapoints that are near a vector of points (represented by a line in the plot). m at master · slavkirov/MPPCdsearchn which are found later in the function are taking considerably more time even thought the size of input to the dsearchn has the same size on all calls. class scipy. In Matlab, the code is. 5+, as well as PyPy 2. Solver-Based Direct Search Basics. Matlabs scatteredInterpolant class similarly allows for linear and nearest neighbour scattered data interpolation. k = dsearchn(P,T,PQ) returns the indices of the closest points in P by using the Delaunay triangulation T, where T = delaunayn(P). Inf is often used for outval. The first version of dsearchn. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. oct-config","path":"scripts/geometry/. to look somewhere carefully in order to find something: 2. Solution. If a point in XI lies. If dsearchn takes a few minutes for one person that might be extremely expensive where a few minutes for another person would be light speed. MATLAB® provides the necessary functions for performing a spatial search using either a Delaunay triangulation or a general triangulation. (Its not n as you say but n+1. The multi-threaded functions. {"payload":{"allShortcutsEnabled":false,"fileTree":{"":{"items":[{"name":"Cohen_MorletWavelets_betterdef. Syntax. For macOS see the installation instructions in the wiki. 1386 and 0. 7K subscribers 1K views 3 years ago A short video on the difference between using find and dsearchn in MATLAB and Octave. In the 4-D example, you can compute the distances, dnn, as follows: [xi,dnn] = dsearchn(X,tri,q); Point-Location Search. Basically they are from the next frame of a movie. If outval is [], then k is the same as in the case k = dsearchn(X,T,XI). For example, I have [-2. 0, cKDTree had better performance and slightly different functionality but now the two names exist only for backward-compatibility reasons. dsearchn Mike X Cohen 25. d is a column vector of length p. KDTree. Something like this: % 2-d data (independent variables) n = 100; X = rand (n,2);This MATLAB function returns the indices of the closest points inside P to the query points in PQ measured in Euclidean distance. For each number in the sequence, the loop prints its value using the print () function. collapse all. Euclidean distances from bsxfun has gotten me the closest, but I'm unsure how to get. KDTree. 创建一些查询点，使用 dsearchn 函数针对每个查询点在 X 间查找与其对应的最近邻点的索引： q = rand(5,4); xi = dsearchn(X,tri, q); nearestNeighbor 方法和 dsearchn 函数允许以可选参数的形式返回查询点与其最近邻点之间的欧几里德距离。 k = dsearchn(P,T,PQ) returns the indices of the closest points in P by using the Delaunay triangulation T, where T = delaunayn(P). EDITED: There would be zero or one value within the range. . Other important factors to consider when researching alternatives to MATLAB include user interface and data analysis. rng default ; P = rand ( [10 2]); PQ = [0. I have a second matrix, B, which is the positions of these points slightly shifted in time. Generally. If xi and yi are vectors, K is a vector of the same size. k = dsearchn(P,T,PQ) returns the indices of the closest points in P by using the Delaunay triangulation T, where T = delaunayn(P). Hey all, I have a simple vector containing my data and wanna find the index of its value closest to zero. According to our records, this is the primary and most recent file release from MathWorks. See also MESH_LAPLACIAN function on matlab central file exchange. For example, T = dfsearch (G,s,'allevents') returns a table containing all flagged. 0 has been released and is now available for download. zeroIX=dsearchn(mydata,0); However, this only gives me the very first value. This is something I want to avoid. See also: dsearchn, tsearch. sort ( [axis, kind, order]) Sort an array in-place. This is a fix to the ismember approach that @Pursuit suggested. scipy. k = dsearchn(X,T,XI) returns the indices k of the closest points in X for each point in XI. The documentation for this function is here: dsearchn v = dfsearch (G,s) applies depth-first search to graph G starting at node s. Image Analyst on 29 Nov 2015. 5]. 1. The first 2 bytes are always 0. . The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. sqrt(np. Currently, both have almost same APIs, and cKDTree is faster than KDTree . Of course, you can perform the above analysis using EEGLAB toolbox, but most of the time you don't even need the toolbox to perform such analysis. {"payload":{"allShortcutsEnabled":false,"fileTree":{"":{"items":[{"name":"README. If outval is supplied, then the values of xi that are not contained within one of the simplices tri are set to outval. Or maybe you could use roots (curve1-curve2). repmat (M,m,n) % matlab np. sort_complex (a) Sort a complex array using the real part first, then the imaginary part. At the moment, I am just doing: Theme. We have a function "dsearchn", which does a N-D nearest point search and returns the indices of the nearest points. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. cKDTree(data, leafsize=16, compact_nodes=True, copy_data=False, balanced_tree=True, boxsize=None) #. T) kdt. I am trying to find points left side of the reference line. create a mesh. f = dsearchn(t',tri,ref) f = 139460. (sûrch) v. This class provides an index into a set of k-dimensional points which can be used to rapidly look up the nearest neighbors of any point. zip","path":"AnalyzingNeuralTimeSeriesData. GNU Octave. Use Report a Concern Form. . To review, open the file in an editor that reveals hidden Unicode characters. Either the number of nearest neighbors to return, or a list of. 在 CPU 和/或 GPU 上并行执行 MATLAB ® 程序和 Simulink ® 仿真. 6. PQ에 포함된 점의 개수가 많을 때 T를 사용하면 탐색 성능이 향상됩니다. % Returns the index @var{idx} or the closest point in @var{x} to the elements{"payload":{"allShortcutsEnabled":false,"fileTree":{"":{"items":[{"name":"README. sort_complex (a) Sort a complex array using the real part first, then the imaginary part. The adaptive coupling PD-FEM model is presented as the third method to solve crack growth in the notched plate. @user3275421 try with knnsearch as suggested above – Sardar Usama. A short video on the difference between using find and dsearchn in MATLAB and Octave. 无需更改任何代码即可实现并行计算，因为已有数百个函数支持自动并行计算和 GPU. 5 0. If XI(J,:) is outside the convex hull, then K(J) is assigned outval, a scalar double. KALYAN ACHARJYA on 25 Oct 2022. Amenta's directory of computational geometry software ; BGL Boost Graph Library provides C++ classes for graph data structures and algorithms, ; CGAL and Leda libraries for writing computational geometry programs and other. Computing this by parallelization in a parfor loop is less efficient, because there is some overhead for starting the threads. spatial. spatial. 2021年8月16日. To identify whether a particular point represented by a vector p falls within one of the simplices of an N-simplex, we can write the Cartesian coordinates of the point in a parametric form with respect to the N. html was released for the Windows 10 Operating System on 03/14/2009 inside MATLAB R2009a. 6 is not a concern, prefer KDTree. However, it can. The whole program intital takes around 400 seconds to run with this one function shown below being the bottle neck taking 350 seconds. ) If the. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. Connect and share knowledge within a single location that is structured and easy to search. sum: For large inputs Matlab computes the sum in several parts using different threads. Issue with estimated computing time Describe the bug: As you can see from row number 186 in the original code file: fieldtrip/forward/ft_inside_headmodel. Two complementary functions tsearchn and dsearchn are also provided to support spatial searching for N-D triangulations. query (x, k = 1, eps = 0, p = 2, distance_upper_bound = inf, workers = 1) [source] # Query the kd-tree for nearest neighbors. The functions tsearch and dsearch perform this function in a triangulation, and tsearchn and dsearchn in an N-dimensional tessellation. The point query is the point PQ (which in your case is a single point but can be a point list) (and which you defined as P but should have been PQ) and the list of points to. g. {"payload":{"allShortcutsEnabled":false,"fileTree":{"scripts/geometry":{"items":[{"name":". Since we are interested in the projectile’s trajectory r, we can then utilise the fact that a. Download and share free MATLAB code, including functions, models, apps, support packages and toolboxesAbstract This paper proposes new machine learning methods based on the representation of classes by convex hulls in multidimensional space, and not requiring the computation of convex hulls or triangulation of multiple points. Note % that the Delaunay triangulation will not be used if a radius % is specified. Providing T can improve search performance when PQ contains a large number of points. Data = [Distance1',Gradient]; Result = Data(dsearchn(Data(:,1), Distance2), 2); Altitude = -cumtrapz(Distance2, Result)/1000; Distance 1 and Distance 2 has different size with same values so I am comparing them to get corresponding value of Gradient to use with Distance 2. k = dsearchn(X,T,XI,outval) returns the indices k of the closest points in X for each point in XI, unless a point is outside the convex hull.