How to write a Float Mat to a file in OpenCV

I have a matrix,

Mat B(480,640,CV_32FC1);

containing floating-point values. I want to write this matrix to a file which could be opened in Notepad or Microsoft Word or Excel to see the values inside and for storage, but the imwrite function can save 8-bit or 16-bit images only...

Could this be done? If yes, how?

Using pure OpenCV API calls:

// Declare what you need
cv::FileStorage file("some_name.ext", cv::FileStorage::WRITE);
cv::Mat someMatrixOfAnyType;

// Write to file!
file << "matName" << someMatrixOfAnyType;

// Close the file and release all the memory buffers
file.release();

The file extension can be xml or yml. In both cases you get a small header that you can easily remove/parse, then you have access to the data in a floating point format. I used this approach successfully (with .yml files) to get data into MATLAB and Matplotlib.

To get the data:

1. open the file with any editor
2. then suppress all the text and numbers, except the content of the data tag (i.e., the pixel values).
3. When done, save your file with a .txt or .csv extension and open it with MATLAB (drag-and-drop works).

Voilà. You may have to reshape the resulting matrix on the MATLAB command line if it didn't guess the image size correctly.