Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
111 views
in Technique[技术] by (71.8m points)

Array of Matrices in MATLAB

I am looking for a way to store a large variable number of matrixes in an array in MATLAB.

Are there any ways to achieve this?

Example:

for i: 1:unknown
  myArray(i) = zeros(500,800);
end

Where unknown is the varied length of the array, I can revise with additional info if needed.

Update: Performance is the main reason I am trying to accomplish this. I had it before where it would grab the data as a single matrix, show it in real time and then proceed to process the next set of data.

I attempted it using multidimensional arrays as suggested below by Rocco, however my data is so large that I ran out of Memory, I might have to look into another alternative for my case. Will update as I attempt other suggestions.

Update 2: Thank you all for suggestions, however I should have specified beforehand, precision AND speed are both an integral factor here, I may have to look into going back to my original method before trying 3-d arrays and re-evaluate the method for importing the data.

Question&Answers:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Use cell arrays. This has an advantage over 3D arrays in that it does not require a contiguous memory space to store all the matrices. In fact, each matrix can be stored in a different space in memory, which will save you from Out-of-Memory errors if your free memory is fragmented. Here is a sample function to create your matrices in a cell array:

function result = createArrays(nArrays, arraySize)
    result = cell(1, nArrays);
    for i = 1 : nArrays
        result{i} = zeros(arraySize);
    end
end

To use it:

myArray = createArrays(requiredNumberOfArrays, [500 800]);

And to access your elements:

myArray{1}(2,3) = 10;

If you can't know the number of matrices in advance, you could simply use MATLAB's dynamic indexing to make the array as large as you need. The performance overhead will be proportional to the size of the cell array, and is not affected by the size of the matrices themselves. For example:

myArray{1} = zeros(500, 800);
if twoRequired, myArray{2} = zeros(500, 800); end

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...