read and write data from .mat file

1 次查看(过去 30 天)
zozo
zozo 2012-3-21
I have a .mat file containing matrix of size 8x3800000.
I need to read 8x980 matrix twice at a time, process it(overlap add technique of convolution) and write back the processed data into a new file.
That is, at a time my RAM should hold only 2x(8x980) data blocks.
How can I do it efficiently? Please help me with the relevant syntax.
Thank you.

回答(1 个)

Wayne King
Wayne King 2012-3-21
Do you have the DSP System Toolbox? You can use dsp.MatFileReader
For example:
filename = [tempname '.mat']; % Create variable name
originalData = rand(100,4);
save(filename,'originalData','-v7.3'); % Write to MAT file
H = dsp.MatFileReader(filename,'VariableName',...
'originalData','SamplesPerFrame', 25);
Y = step(H);
Each time step() is called you get 25x4 out of the 100x4 matrix.
  5 个评论
Wayne King
Wayne King 2012-3-21
You have to contact MathWorks for that. If your version of MATLAB is on maintenance, you should be able to just download R2012a. I don't know what your licensing situation is, so contact MW.
zozo
zozo 2012-3-21
How can I only write data into file sequencially after processing? For example: At first, I have two blocks of length 1024, I overlap(44 samples in head and tail) and add them, then save(write) the first 1024 in a file. Then I do the same for 2nd and 3rd blocks and save the 2nd block behind the first block (and so on..) How can I do this?

请先登录,再进行评论。

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by