Converting MATLAB Binary file to Eigen Sparse Matrix

I am new to C++ and want to use the Eigen library to solve some sparse linear algebra problems. I have my arrays however they are MATLAB mat. files, and so I have loaded them into binary files like so:

%write data to binary file
dataA = A;
fid  = fopen('FileA.bin', 'w');
if fid == - 1
  error('Cannot open file for writing');
end
fwrite(fid, ndims(dataA), 'uint16');
fwrite(fid, size(A), 'uint64');
fwrite(fid, dataA, 'double');
fclose(fid);

This code seems to have worked and my variables are safely stored in .bin files. How could I read these files into Eigen Sparse Matrices?