To initialize an N-by-M matrix, use the “zeros” function. For example, create a 3-by-5 matrix of zeros:
A = zeros(3,5);
You can then later assign specific values to the elements of “A”. Answer from Leah on mathworks.com
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Matrices and Arrays - MATLAB & Simulink
All MATLAB variables are multidimensional arrays, no matter what type of data. A matrix is a two-dimensional array often used for linear algebra. To create an array with four elements in a single row, separate the elements with either a comma (,) or a space.
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Creating, Concatenating, and Expanding Matrices - MATLAB & Simulink
Then, create a 4-by-4 matrix whose diagonal elements are the elements of A. ... The createArray function (since R2024a) can return arrays of almost any MATLAB data type. The function uses the same syntax as zeros and ones to define the size of the array, but it also offers several options for specifying the contents of the array.
Creating a matrix of specific size, in which I can input each element value.
I would like to create a matrix of a Nx1 size where I can input the value of each the "N" elements of the matrix automatically. For example, if I want a 4x1 matrix, I would like to be able to input the first element, second and so forth manually. Thanks for the help and I hope I made myself clear. ... https://www.mathworks.com/matlabcentral... More on mathworks.com
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September 16, 2018How to create a matrix of size N×N that has ones in the border and zeros inside?
Create a matrix of size N×N that has ones in the border and zeros inside. For example, if N=3 the matrix can be created with ... Make this construction depend on N and work for any positive integer N≥2. Sign in to comment. Sign in to answer this question. ... https://www.mathworks.com/matlabcentral... More on mathworks.com
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September 6, 2017How to create a matrix with arbitrary dimensions
https://www.mathworks.com/matlabcentral/answers/446034-how-to-create-a-matrix-with-arbitrary-dimensions#answer_361913 ... To create an zero array of an arbitray dimensions between 1 and D with arbitry sizes between 1 and S : More on mathworks.com
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February 20, 2019how to generate matrix of size 10X10?
how to generate matrix of size 10X10?. Learn more about matrix MATLAB More on mathworks.com
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March 26, 2014Generate Different Types of Matrices with MATLAB Commands
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How to Create a Matrix of Set Size with Random Numbers Between ...
03:30
Creating Matrices of Ones and Zeros in Matlab - YouTube
19:04
Analyze Vector and Matrix in MATLAB | Length| Size| Sum| Min| Max| ...
01:03:13
Lecture 8: Matrix Manipulations | Exploring MATLAB - YouTube
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To initialize an N-by-M matrix, use the “zeros” function. For example, create a 3-by-5 matrix of zeros:
A = zeros(3,5);
You can then later assign specific values to the elements of “A”.
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I am assuming you are trying to create an empty matrix of zeros of dimensions N*M. You can try the following instead
M = zeros(3,3)
This creates a matrix of zeros of size 3*3.
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Creating a matrix of specific size, in which I can input each element value. - MATLAB Answers - MATLAB Central
September 16, 2018 - Hello Everyone, I would like to create a matrix of a Nx1 size where I can input the value of each the "N" elements of the matrix automatically. For example, if I want a 4x1 matrix, I would like ...
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Creating Matrices and Arrays - MATLAB & Simulink
To create an array with multiple ... in a single column: >> a = [1; 2; 3; 4] a = 1 2 3 4 · To create a matrix that has multiple rows, separate the rows with semicolons....
Ubcmatlabguide
ubcmatlabguide.github.io › html › matrixOperations.html
Operations on matrices
The spy() function can be used to visualize the sparsity pattern of a matrix. The spalloc() function can be used to preallocate space for a sparse matrix. The following command creates a 100-by-100 matrix with room currently for 10 non-zero elements. More than 10 non-zero elements can be added later but this can be slow as Matlab will need to find a larger chunk of memory and copy the non-zero elements.
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How to create a matrix with arbitrary dimensions - MATLAB Answers - MATLAB Central
February 20, 2019 - https://www.mathworks.com/matlabcentral/answers/446034-how-to-create-a-matrix-with-arbitrary-dimensions#comment_673463 ... You want a Sz-by-Sz-by- ... -by-Sz array, where Dims specfies the number of Sz's
GeeksforGeeks
geeksforgeeks.org › matlab-matrix
Matlab - Matrix - GeeksforGeeks
February 21, 2022 - In MATLAB, the matrix is created by assigning the array elements that are delimited by spaces or commas and using semicolons to mark the end of each row. Now let's have a glance at some examples to understand it better.
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mathworks.com › matlabcentral › answers › 123126-how-to-generate-matrix-of-size-10x10
how to generate matrix of size 10X10? - MATLAB Answers - MATLAB Central
March 26, 2014 - I have generated the numbers from 1 to 10 by using the command 1:1:10. I got 1X10 size matrix but I want the matrix of size 10X10 i.e, each column values should be same. Please help me. ... https://www.mathworks.com/matlabcentral/answers/123126-how-to-generate-matrix-of-size-10x10#comment_204265
Reddit
reddit.com › r/matlab › how do i make a fixed size array/matrix from a given dimension through variables?
r/matlab on Reddit: How do I make a fixed size array/matrix from a given dimension through variables?
June 13, 2021 -
I need to be able to create a matrix or pre-allocate a matrix from given ROW and COLUMN inputs. I've found that if I do something like:
a = zeros(10,12)
SIMULINK grants it as a fixed size matrix.
But if I do stuff like following:
function y = matrix(row,col)
a = zeros(row,col)
y = a
SIMULINK thinks the dimensions are variable. Thus it's a variable sized matrix. So I can't wire the output to another block which wants fixed size matrix.
What is the solution here, if I want to take my matrix dimensions from variables?
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Published: August 21, 2018
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mathworks.com › matlabcentral › answers › 113341-matlab-function-for-defining-the-size-of-a-matrix
Matlab function for defining the size of a matrix - MATLAB Answers - MATLAB Central
January 22, 2014 - The size of matrix A (in the model) is 14x14 B= 14x2 C= 14x14 D= 14x2 Now I need to know, how to use the function below to make the size of matrix B as 14x2 B=zeros(size(A,1),1) Please d...
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mathworks.com › matlabcentral › answers › 121976-how-can-i-create-an-array-of-fixed-length
How can I create an array of fixed length? - MATLAB Answers - MATLAB Central
March 17, 2014 - https://www.mathworks.com/matlabcentral/answers/121976-how-can-i-create-an-array-of-fixed-length#comment_483021 ... @Akshay Joshi: You will have to either check the indices before allocating, or check the vector size after allocating.
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40000 * 40000 * 8 bytes per number = 12 GB, surely you won't have enough memory.
To create a huge matrix with lots of zeros, you need a sparse matrix:
m = sparse(40000, 40000)
To create an array of variants, you can use a cell array:
m = cell(3, 1)
m(1) = [1,2,3]
m(2) = [2,4,6,8,10]
m(3) = 6+6i
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There are many things you can do, as the various answers point out. The correct answer depends on your actual problem. Brute force creation of such a large array is impossible without a 64 bit version of matlab plus enough memory to store that large an array, or storing the array in some other way. You can store the array offline, only bringing in what you need as you use it.
For example, if these numbers will always be small integers, then use uint8 or int8, or a logical array, even a single array, all of which will reduce the memory requirements compared to double arrays. Or use a sparse storage form as appropriate. Much depends on what you will do with the array.
As far as a variable number of elements in a row, use a cell array here, not a flat traditional array.
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mathworks.com › matlabcentral › answers › 423738-how-to-predefine-a-matrix-with-one-unknown-dimension
how to predefine a matrix with one unknown dimension - MATLAB Answers - MATLAB Central
October 12, 2018 - Just define a matrix that's well large enough to hold all your numbers, like a few million elements or whatever. ... Then do whatever you need to do assigning rows and columns in v, then, if you've kept track of the max column number, you can ...
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ones - Create array of all ones - MATLAB
X = ones(n) returns an n-by-n matrix of ones. ... X = ones(sz1,...,szN) returns an sz1-by-...-by-szN array of ones where sz1,...,szN indicates the size of each dimension.
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Empty Arrays - MATLAB & Simulink
In most cases where you need to create an empty array, a 0-by-0 array is sufficient. However, you can create empty arrays of different sizes by using functions like zeros or ones. For example, create a 0-by-5 matrix and a 3-by-0-by-5 array.
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Create a matrix of matrices - MATLAB Answers - MATLAB Central
October 19, 2021 - Currently this is done by stacking the constituent matrices into a master matrix, but calling the values requires the index be increased/decreased by a multiple of one of it's lengths (depending on how it's constructed).