[irs) ĭisp('checking for wrong matches: should all be empty. ![]() Otherwise I could use the distance matrix and just look for all entries below a tolerance, e.g., 1E-10. Some data sets have points matching perfectly, others have some distance between matching points. It does not have to be sorted according to distance. I want to know the pairings, which for my data match more or less uniquely. List all distinct pairs (black,coloured) formed by points in the first and points in the other set, sorted by their distance?Īlmost. Irs, ics = I could not use BitSet() or Set(), since I need to know the order of the points, which I use later for mapping some fields. Lk = 4 # 1 relative set, 3 working data sets # get distance matrix A i relative points, j points to be mapped # pick pairs of smallest distance and return corresponding points (or their order) Just in case anybody is interested, the solution looks like this: using Random Now Julia outperforms MATLAB by almost an order of magnitude. I tried to do the same in MATLAB, but maybe in this case I have done it less efficiently. Now you just need to filter out which rows/cols have already been seen, perhaps something like julia> is, js = BitSet(), BitSet() Julia> CartesianIndices(A0)ĬartesianIndex(3, 2) # first, eliminate 3,2 Can’t you avoid this entirely, perhaps call sortperm(vec(A)) which takes 240ms, but only 3 times? A sketch: julia> A0 = rand(Int8, 3,3) This takes 7.4ms, times 1500 times 3 gives about 30s, which is how long (a slightly improved) version takes to run. Any suggestions how I can speed up the code?Īs you say, all the time is in argmin(A). In reality Lp is greater than 1500, which is a real problem for me. I also tried findmin(A), but the performance is the same. # pick pairs of smallest distance & clear these pairs from Aįinding the minimum takes almost all the time and I was wondering if Julia with argmin(A) is maybe faster than MATLAB’s min(A). # create test data: coordinates of relative points and points to be mappedĪ = A + (pload*ones(1,Lj)-ones(Li,1)*pload').^2 However, there are a few cases when ismember does ignore trailing spaces: If A is a character array and B is a cell array of character vectors, then ismember ignores trailing spaces in the character array.I ported a code from MATLAB to Julia, because it takes too long right now: using Random ![]() Does ismember ignore trailing spaces in an array? For timetables, ismember takes row times into account to determine equality. If A and B are tables or timetables, then ismember returns a logical value for each row. For those elements of A that do not occur in S, ismember returns 0. = ismember (A, S.) returns index vector loc containing the highest index in S for each element in A that is a member of S. Then it calls an internal binary search routine passing in A and sorted B average complexity of that is probably length (A) log2 (length (B)). If necessary it sorts it, which does not apply in your described case. If the elements are present, then it returns 1 (True) else it returns 0 (False). The ismember code first checks the array with issorted (B), which is O (length (B)). Please find the below syntaxes which are used in Matlab considering ismember function: Lx=ismember (X, Y): This checks whether the elements in X is present in Y. The result is in the form of logical 1 (True) or logical 0 (False). The elements of the cell array must all contain the same data type, and the resulting array is of that data type. How do you turn a cell array into a matrix in MATLAB?Ī = cell2mat( C ) converts a cell array into an ordinary array. You can set TOL on the Calculation tab, in the Worksheet Settings group, or directly in the worksheet. ismembertol treats elements that are within tolerance as equal and determines that all of the elements in x are members of y. Look at how the system variable Convergence Tolerance (TOL) affects the results of definite integrals. Use ismembertol to perform the comparison using a small tolerance. This tells scikit to stop searching for a minimum (or maximum) once some tolerance is achieved, i.e. What is tolerance Tol?Īs you noted, tol is the tolerance for the stopping criteria. Elsewhere, the array contains logical 0 ( false ). ![]() In your case you want to print letters so if you use %f formatspec you won’t get the desired result. Lia ismember (A,B) returns an array containing logical 1 ( true) where the data in A is found in B. %s represents character vector(containing letters) and %f represents fixed point notation(containining numbers). Then ismembertol uses the resulting scaled comparison tolerance to determine which elements in A are also a member of B. ismembertol scales the tol input using the maximum absolute values in the input arrays A and B. Tol - Comparison tolerance Comparison tolerance, specified as a positive real scalar.
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