How do I find first index of a value in an array?. But if you want to extract row and column you just need to adapt the code Jan gave you. Learn more about interpolation, find, array https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_692300, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_692308, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_1259273, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#answer_370203, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_693180, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#answer_370022, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_692437, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_692620, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#comment_692755, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#answer_411503, https://la.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array#answer_547788. Hence I used it to find the next value greater than the one you want and did the required maths from there. To find the indices of all the locations where the maximum value (of the whole matrix) appears, you can use the "find" function. # Get the maximum value from complete 2D numpy array maxValue = numpy.amax(arr2D) It will return the maximum value from complete 2D numpy arrays i.e. Therefore I am looking for find() type function that would do the job. https://www.mathworks.com/matlabcentral/answers/365917-how-i-can-find-index-of-element-in-array#answer_290079, https://www.mathworks.com/matlabcentral/answers/365917-how-i-can-find-index-of-element-in-array#comment_502775. When 'linear' is specified, I contains the linear indices of A corresponding to the maximum values. Look up logical indexing in matlab for more details. Whenever I've wanted to find the index of a specific value I subtract the value of the element I want then take the min() of the abs() of that. assume the matching value is 205; location or order in this case should be 4. You can perform these tasks using a combination of the relational and logical operators. I know, that number, for example, 5, is an element in array X, but I don't know it's index. The findIndex method executes the callback function once for every index 0..length-1 (inclusive) in the There's probably neater ways to do it too, or shorter, at least! Based on your location, we recommend that you select: . Start Hunting! Also note these formulas will fail if there are duplicate values in the array. Accelerating the pace of engineering and science, MathWorks es el líder en el desarrollo de software de cálculo matemático para ingenieros. I know, that number, for example, 5, is an element in array X, but I don't know it's index. Find the index of given value in an array. Is there any other way to find the min value other than zero and also to find its index… [i,j] = find(X) returns the row and column indices of the nonzero entries in the matrix X.This is often used with sparse matrices. Indexing: vectors in MATLAB are not the same as in every other programming language because the indexing starts from one instead of zero, which means that the first value has the index one. It isn't magic. To find array elements that meet a condition, use find in conjunction with a relational expression. Thank you for your answer. It can contain only 1. Reload the page to see its updated state. https://www.mathworks.com/help/matlab/ref/find.html maximum = … The value of the maximum where the logical index is zero, is left out. my array is [114 205 137 205 144 204]. The code example also defines a search predicate method named EndsWithSaurus, which accepts a string parameter and returns a Boolean value indicating whether the input string ends in … k = find(X) returns the indices of the array X that point to nonzero elements. Find the treasures in MATLAB Central and discover how the community can help you! You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. I have made an array of doubles and when I want to use the find command to search for the indices of specific values in the array, this yields an empty matrix which is not what I want. One is temperature and the other is time both start at 2017,1,1,00,00,00 and end at 2017,12,31,23,50,00 with a 10 minutes sample. I is the same size as the first output.. MATLAB returns an array that matches the elements of the array X, element-by-element holding 1s where the matching values in X are the desired values, and 0s otherwise. To directly find the elements in X that satisfy the condition X<5 , use X(X<5) . You may receive emails, depending on your. Find max value in complete 2D numpy array. 17 I have two series both with 52560x1 size. In Python, I can use: How to find index of a value in cell array. 0. You can either use the find function or use the comparison operator as an index like A(A>10). When 'linear' is not specified, I is the index into the operating dimension. You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. Choose a web site to get translated content where available and see local events and offers. But unfortunately 33spm is not in the array 34.8 is which is the closest to 33. 0. 2. Tags find array same value; See Also. u=unique(a) ... Find the treasures in MATLAB Central and discover how the community can help you! i have to find the index of the same value in an array,see the following example. Giving what people call a 'Minimum working example' is fine, but it needs to have the full complexity of what you actually want to know still, otherwise it's of no use. For instance, you can examine the even elements in a matrix, find the location of all 0s in a multidimensional array, or replace NaN values in data. Histogram in Matlab for data bigger than a threshold. in all rows and columns. This is a manual approach and probably would cause bugs in my case cuz the original code I am running is much more complicated in a numerical sense. Start Hunting! Find the index of given value in an array. I assume the problem lies in the precision of the values and/or decimal places that are not shown in the readout of the array. That's it, 4 is all what I want. [EDITED] If you are talking of a cell string, this is much faster: D = {'1' '5' '3' '4' '2' '3' '4' '5' '2' '1'}; index = find (strcmp (D, '5')); Syntax. Find indices and values of nonzero elements. arrays matlab Afterwards the final max() finds the maximum of the above, which corresponds to the second maximum. Note: this answer is based on the original answer by madhan ravi: https://web.archive.org/web/20190410151058/https://www.mathworks.com/matlabcentral/answers/455509-find-the-index-of-given-value-in-an-array. How to find the index in array?. If you bother to write a comment, you can write the answer instead of advising on how to write a question. This example shows how to filter the elements of an array by applying conditions to the array. It cannot contain 3 vectors and a scalar unless they parts of a single variable like a structure or table variable. To find maximum value from complete 2D numpy array we will not pass axis in numpy.amax() i.e. I want find a particular value (let's say 7) in the first column, and then use the reference to get at the text value in the same row (much like VLOOKUP in Excel). I had a manual code but then realized yours is shorter and I will be using that one. MathWorks is the leading developer of mathematical computing software for engineers and scientists. It can't find things that don't exist. You should always give an example that shows the full complexity of the question you are asking though if you want a useful answer. Often logical indexing is more efficient, so you might only need this: You may receive emails, depending on your. Find the indexes of duplicate values and replace their indexes in Matlab. idxFract = idxAboveVal - ( array( idxAboveVal ) - val ) / ( array( idxAboveVal ) - array( idxAboveVal - 1 ) ); Obviously it would need error checking if idxAboveVal is 1 or empty. cell array find MATLAB. The linear index of 5 is 4 not 5! In Python, I can use: I realized this function, using for loop and if statement, but did Matlab doesn't have build-in similar function? For example, find(X<5) returns the linear indices to the elements in X that are less than 5 . Other MathWorks country sites are not optimized for visits from your location. Choose a web site to get translated content where available and see local events and offers. ... find longest continuous array with values exceeding a threshold. 0. Learn more about interpolation, find, array Reload the page to see its updated state. a=[1 2 3 1] i want b=[1 4] as output..how can i do this? Tags cell arrays… Accelerating the pace of engineering and science. MATLAB: Find a value with cell array. What I want are the indices where the value -1 occurs, since I have to replace them afterwards. It does work! When you ask a question , make sure you give an example clearly instead of advising others how to answer the question. I already know that the perfect outcome of one of these values is 33spm. Other MathWorks country sites are not optimized for visits from your location. Yeah, I was originally going to give an answer based on interp1 but had a brainfade on working out how to use it for this! A solution using find is this. I know, that number, for example, 5, is an element in array X, but I don't know it's index. The structure of the cell array is like this: A is a 27x1 cell where each of the 27 rows has 500000 cell entries (numeric values between -1 and 999). 0 ⋮ Vote. I got the value using the following code but I have the nan value in pbest in loops it is giving errors. Hello, I have an array with 20 values of steps per minute. Based on your location, we recommend that you select: . ... Find the treasures in MATLAB Central and discover how the community can help you! Unable to complete the action because of changes made to the page. Learn more about index of element MATLAB, Image Processing Toolbox Follow 508 views (last 30 days) Vishal Sharma on 25 Jan 2017. Column Vector: to define a column vector, you can either separate every element with a semi-colon (;), or you can define the vector and use the transpose function, as we will see in the following sections: The array logInd is not an array of double numbers, but have the class logical . index = cellfun (@ (x) x==5, C, 'UniformOutput', 1); Or the long and most likely faster form: index = false (1, numel (C)) for k = 1:numel (C) index (k) = (C {k} == 5); end. Given an array of known point values (Xpoints), which is a 1 x 11 array I'm trying to search and generate a list of index locations that correspond to when the X_ValueTrans (1 x 501) equals the individual elements in the Xpoints array. Learn more about index, indexing, matlab function, homework I need to find the index for the minimum value in pbest other than '0'. It can't find things that don't exist. ... Are there any functions that will return the index of … matlab: find the index of rows from the first matching column value. It isn't magic. I want to find fractional index when array == 2.5 or any other intermediate value. I want to extract both temperature and time for elements starting at 2017,4,15,00,00,00 and ending at 2017,4,30,23,50,00. A cell cannot contain more than one variable. Unable to complete the action because of changes made to the page. The find function simply finds integer indices into an array that correspond to the logical expression you give it. What is the code to find the value closest to 33? And compared to the (very complex) accepted answer: >> idxAboveVal = find( array >= val, 1 ); >> idxFract = idxAboveVal - ( array( idxAboveVal ) - val ) / ( array( idxAboveVal ) - array( idxAboveVal - 1 ) ). A manual approach to things causes bugs if you get it wrong, not if you get it right. Much simpler (and also works for multiple. Find the index of given value in an array. Find the treasures in MATLAB Central and discover how the community can help you! k = find(x) [i,j] = find(X) [i,j,v] = find(X) Description. For example, the following code produces a row vector 'M' that contains the maximum value of each column of 'A', which is 3 for the first column and 4 for the second column. I have some problems to get the indices of a certain value, in this case -1, within a cell array. Compare the temporary "distances" array to that minimum value (resulting in some binary array), and then use find to get the corresponding indices, which finally can be used to get the values from the original input array x. In Python, I can use: Store the row and column return from find and put it in the match cell array. command: peaks=find(y1==0.8236) An array of strings is created, containing 8 dinosaur names, two of which (at positions 1 and 5) end with "saurus". If none is found, find returns an empty matrix. Find max value & its index in Numpy Array | numpy.amax() Python: Check if all values are same in a Numpy Array (both 1D and 2D) Python Numpy : Select elements or indices by conditions from Numpy Array; How to Reverse a 1D & 2D numpy array using np.flip() and [] operator in Python; xpts = [0 0.0004 0.0011 0.0018 0.0025 0.003]; x = 0:0.0001:0.003; index1 = find(ismember(x, xpts)); It returns index1 = [1 5 12 26 31] but there is one more element '0.0018' in x which also belongs xpts, and not including in the answer. Once your data is available in MATLAB Workspace, you can then perform any operations you desire including finding values and their indices which are greater than 10. Please show the expected output for your example values. Vote. Note: for this example, we are arbitrarily find the location of the maximum value in the data, but you can replace data=MAX(data) with any other logical test that will isolate a given value. Thanks! Learn more about interpolation, find, array The find function simply finds integer indices into an array that correspond to the logical expression you give it. In Python, I can use: Index, returned as a scalar, vector, matrix, or multidimensional array. Hence I used it to find the next value greater than the one you want and did the required maths from there. 0. I know, that number, for example, 5, is an element in array X, but I don't know it's index. The "min" and "max" functions in MATLAB return the index of the minimum and maximum values, respectively, as an optional second output argument. find.