I wanted to get rid of those loops but still have no idea on how to do so. I want to replace 1 in each row with column index value. I would like to replace certain values (all at multiple indices) with 1 (there is no value of 1 in the original matrix) and the rest with zeros- but in a much more efficient way. By continuing to use this website, you consent to our use of cookies. Any idea on how to do that? Values are ordered from the smallest value to replace with to the largest, i.e., to replace 12 with 41, 25 with 26 and 40 with 13 defise Avalnew as. This does work for a single value. These IDs are given to each pixel by the mask matrix. Here is a small example using the following content. matrix matrix manipulation replace. Thanks. Based on your location, we recommend that you select: . Find and match multiple values in a matrix with MATLAB's ismember function I was preparing some results of an image segmentation algorithm for publishing and needed a way to find all pixels that match a variable set of multiple numbers (e.g. in the end, I want to get the result: Much appreciated. My problem is that I have some flow measurements, and I need to remove all values below 0.01 l/s, so Q>0.01 l/s. Hello I've just started using Matlab few months ago so I hope somebody can help me with my problem. I think I need a little more info on your code. Share. Accepted Answer . While it is a handy one-liner, it does not have the time-savings of moving from a looped function to an matrix-operation function. Replace 'greater than' values in a matrix. I put in a loop over the colors, but since that is only 3 iterations, that will not cause any issues. I have a large matrix and in the fifth column I want to replace every value of 990 with 30.375, how could I do this easily? I do the same with the other columns when max(k)=1. Thank you very much. Reload the page to see its updated state. *color(3); No idea if it will bring any performance improvements in the end :-). I have a sample array a=[3 2 5 7 4 8 2 5], I would like to replace all numbers greater than 5(>5) to be 5, the expected result … To replace all NaN elements of the matrix B with zero, use. MATLAB: How to substitute multiple values in symbolic matrix. 0 Comments 25 25 40 40 40 40 40 25 25 25. Would appreciate any help. You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. I would like to replace these with NaN throughout the entire table. Replace 'greater than' values in a matrix. 1 ⋮ Vote. Replace '22' using regexprep. 1. 25 40 40 40 40 25 25 25 25 25. find all elements in the array a that has value 1 or 2). You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. Accelerating the pace of engineering and science. Thank you very much. One is an image, the other one is as big as the image with only one dimension. Hello everyone, I am new in matlab and I need help please. Active 3 years ... % build an indexer to the elements equal to 1 in column 5 X = num2cell(X); % convert the matrix into a cell array X(idx,5) = {[-3 5]}; % replace the indexed elements with a vector Share. I would like to replace certain values (all at multiple indices) with 1 (there is no value of 1 in the original matrix) and the rest with zeros- but in a much more efficient way. gooniyath on 15 Aug 2016. I have a 91282x1 (d) array with a lot of different values. You may receive emails, depending on your. For example, you could replace all the NaN elements in an array with another value by using a combination of isnan, logical indexing, and scalar expansion. Define the new values. With function subs, we can substitute only single value in expression. Follow 23 views (last 30 days) Patrick Rausenberger on 5 Aug 2019. Many MATLAB functions that start with is return logical arrays and are very useful for logical indexing. Best Answer. Follow 3.054 views (last 30 days) Show older comments. Very flexible and smart solution! B(isnan(B)) = 0 idx=(colNos-1)*size(z, 1)+rowNos; z(idx)=0 Flatten the z-matrix and access it through a linear index, which is a combination of rowNos and colNos. The problem is the "status" columns have "NULL" values as their first few values, but the columns are all different, ie. Other MathWorks country sites are not optimized for visits from your location. For example, I have an 2d array A as of 1000x1000, of all zero values. Commented: Javier Cabello on 17 Apr 2020 Hi, I have a matrix similar to this: A =[ ] 25 40 40 40 25 25 25 25 25 25. In my case it is a labeling of the image. Say my N is a 6x6 matrix with 5 symbolic variables and I want to evaluate N at one go, for 5 different values of the variables. Vote. ind=sub2ind(size(im),x,y,color_channel*ones(n,1)); Thanks, ismember seems to do the trick ;-), You may receive emails, depending on your. The first one. Reload the page to see its updated state. Skip to content. https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#answer_231757, https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#comment_385364, https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#answer_231776, https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#comment_830105, https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#answer_365001, https://de.mathworks.com/matlabcentral/answers/299597-replacing-values-in-a-matrix#comment_680166. Accepted Answer: Azzi Abdelmalek. how to do that? But how to make first code work with decimal values i.e. Vote. Thanks. *color(2); b(mask==toReplace(c)) = o(mask==toReplace(c)). How to replace multiple values in a matrix in matlab. I have a sample array a=[3 2 5 7 4 8 2 5], I would like to replace all numbers greater than 5(>5) to be 5, the expected result should be a=[3 2 5 5 4 5 2 5]. I have a matrix A that contains probability distribution( size : 7*8).there is the matrix : A=[ 0.2 0.07 0.25 0.87 0.09 0.14 0.8 0.3; How do I write a script to replace all the 25's, with a certain value, and the 40's with another value and 12's with another value? I want to clean up and replace all those values with NaN. 0. 1 Comment Show Hide all comments 0. how to replace the element in matrix?. I don't mean to get a 5*5 all 0 element matrix eventually. This website uses cookies to improve your user experience, personalize content and ads, and analyze website traffic. I want to replace the number of a column based on the values of two preceding columns and change the number it has to something else. 3,183 2 2 gold badges 16 16 silver badges 16 16 bronze badges. Show Hide -1 older comments. Replace all values in a matrix that fall within some range of values Does anyone know of a simple way to change all values (x) in a matrix that fall into a range a