Creating a new matrix and insert certain values into that matrix
I suspect that you are asking about SUB2IND: R = [1,3,3,2,2,3,3,4,3]; C = [1,1,1,3,4,1,2,1,4]; V = [2,2,2,4,2,3,3,2,1]; M = ...

24 dagar ago | 0

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Strings to variable names
Mixing up unrelated topics has made you think that this is much more complex than it really is. Look at your own code that you ...

26 dagar ago | 1

Random Number from a given vector of numbers
V = [-1,23,99,111,1024]; N = 3; A = V(randi(numel(V),1,N)) % with repetition B = V(randperm(numel(V),N)) % no repetition

27 dagar ago | 1

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How do I reformat a set of differently formatted dates in to one consistent format?
There is no tool which will correctly interpret the mutually-exclusive date formats used around the world: https://en.wikipedia...

29 dagar ago | 0

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Rewriting code without loops
Fake data: dev = rand(101,1); GradW = rand(4,101); HessW = rand(4,4,101); Your code: A = zeros(4,4,101); for i=1:101 ...

29 dagar ago | 0

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How to zero mean a 3-D array
The simple MATLAB approach: S = load('matlab.mat') A = S.A A = A - mean(A,2:3)

29 dagar ago | 0

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Won't show me my variable?
"What can I change to fix it?" Use logical indexing, e.g.: I = 0.5 * Ms; X = Ms>=3.5; I(X) = 21.29 * Ms(X) - 69.4; X = Ms>=...

29 dagar ago | 0

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Extract specific field names and associated data from a structure
Rather than using an IF it would be simpler to specify an appropriate filename for DIR: P = 'myfile'; S = dir(fullfile(P,'*bf_...

30 dagar ago | 0

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How can I extract the same variable from multiple files & concatenate them efficiently?
"I just can't seem to figure out how to efficiently extract a u and v vector from each file within the loop using my function be...

ungefär en månad ago | 0

Replace empty string with NaN in a cell
A = {"20","25","25",[],"20",[],"25","25","25","30"} A(cellfun(@isempty,A)) = {"NaN"} Using one string array is likely much bet...

ungefär en månad ago | 0

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copying specific elements of an array to another.
Forget about loops, the simple and efficient MATLAB approach is to use logical indexing: g = y(y>0.001)

ungefär en månad ago | 1

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how to shift rows to right and left of matrix ?
M = [1,2,3;4,5,6;7,8,9] A = [3,2,1]; B = [2,5,2]; c = [4,1,3]; for k = 1:size(M,1) if A(k)<B(k) %shift row to right wit...

ungefär en månad ago | 0

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How to create a pivot table from this table, Part 2
customer = {'Customer 1';'Customer 2';'Customer 3';'Customer 4'}; location = {'NY';'LA';'Austin';'LA'}; gender = {'male';'fe...

ungefär en månad ago | 0

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Doubt regarding max(A,B).
"Why is max(A,B) as [10 6 5]?" Because that syntax provides an element-wise comparison of the two input arrays, taking the maxi...

ungefär en månad ago | 3

changing the existing variables on the for loop
abc = [1,3,5,7]; k = abc; r = abc; for ii = 1:5 [r,k] = deal(k+3,r+5) end

ungefär en månad ago | 0

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how to use for loop for iterations in matrices?
"how to use for loop for iterations in matrices?" Do NOT number the variable names, unless you want to force yourself into writ...

ungefär en månad ago | 0

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Assigning an arbitrary number to an array
x = [2.32, 4.23, 1.92, 3.24, 2.13]; points = [3, 1, 2]; first_answer = x(points); [second_answer,idx] = min(first_answer); t...

ungefär en månad ago | 0

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Sort column vectors of a matrix and extract a new vector from a maximal criterion
M = [1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2; 1,1,1,1,2,2,2,2,4,4,4,1,1,1,2,2,2; 1,2,3,4,1,2,3,4,1,2,3,2,3,4,1,2,3; 31,16,15,9,10,8,13...

ungefär en månad ago | 0

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Assignment in a for loop
"Any suggestion how to solve this simple looking problem?" Use a non-scalar structure: https://www.mathworks.com/help/matlab/m...

ungefär en månad ago | 0

How to save local variables (which are within a called function)
"...there are some variables (calculated inside the function @ODE_System) and i would like to see and save their values along wi...

ungefär en månad ago | 0

How to do matrix Preallocation?
"what am i doing wrong?" You are concatenating the new data onto the bottom of your preallocated matrix, rather than using inde...

ungefär en månad ago | 0

what does a = T(m:m, 'label'); mean?
"what does a = T(m:m, 'label'); mean?" It refers to row m of variable/column "label" of the table T, returning a table: https:...

ungefär en månad ago | 1

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A query relating a function with 3 input arguments.
"Why is the answer '-21' and not '-9'?" Because this code x>y>z is parsed from left to right as (x>y)>z which (because true...

ungefär en månad ago | 1

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Functional programming construct to expand cell array into arguments for other functions without using an intermediate variable in the (user) code?
The closest is to use the new syntax which allows dot indexing directly into function outputs: https://www.mathworks.com/help/m...

ungefär en månad ago | 0

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Constructing names of array and structure variables
"I'm trying to dynamically create variable names, for array and struc variables" But your example shows you changing a structur...

ungefär en månad ago | 1

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Regular expression: how to search for a sequence of one number alternated with 0s?
S = '5ad3515505546151g545460000051333300342511324sgfb15654404440044532152331450005534563asdf4453415364043344004044453'; C = reg...

ungefär en månad ago | 2

Split comma seperated values inside a cell in to multiple columns
Simpler and more efficient: % load your data: S = load('split_mat.mat'); C = S.split_mat; % convert to numeric: F = @(t)ssc...

ungefär en månad ago | 0

How to remove all the rows containing a substring from a table?
Simple and efficient MATLAB approach: A = [0;1;2;3;4]; B = ["cat";"hat";"sat_Downstream";"fat";"rat_Downstream"]; C = [5;6;7;...

ungefär en månad ago | 0