This is an example of the format used to store the rfMRI full correlation matrix with dimension 25. Data consists of a series of floating point numbers separated by space characters.

This resource can be downloaded or viewed using the link: d25fulcor.txt

If you have wget available (typically on linux systems), then you can also obtain a copy using the command

 wget  -nd  biobank.ndph.ox.ac.uk/ukb/ukb/examples/d25fulcor.txt