4D matrix in .txt and .csv

I have 4D data which are 3D images + time. Data = [256,256,22,99]. I would like to save it in text file and .csv. How can I do this?

[Lin]

Is there any update answer for this question?

Answer 1

[Miriam]

You could reshape your data (https://www.mathworks.com/help/matlab/ref/reshape.html) into a 2D matrix (something like [256x256x22,99]). If you want you could also save the 3 xyz coordinates (i.e. indices) in the matrix (size [256x256x22,3+99]).

To save as .txt, try dlmwrite (https://www.mathworks.com/help/matlab/ref/dlmwrite.html)

To save as .csv, try csvwrite (https://www.mathworks.com/help/matlab/ref/csvwrite.html)

[Mar]

Why should I reshape my data? Are already 4D.

[Miriam]

dlmwrite() and csvwrite() will reshape your data into a 2D matrix anyway; if you reshape it yourself you'll have more control over the final format. To my knowledge there is no way to save a 4D dataset in .txt or .csv. You could save it as a 4D .mat variable using save().

[Valeriy]

Thanks Miriam for your answer. Did I understand right, that if I have 4D matrix, 3 dimensions of which are space coordinates (x,y,z) and in each voxel I have some value, intensity of something, for example, so as you told:

>If you want you could also save the 3 xyz coordinates (i.e. indices) in the matrix (size [256x256x22,3+99]).

Is it correct? Could you precise, how it is possible to realize?