Vector sq = SSVDHelper.loadAndSumUpVectors(sqPath, conf);
Vector sb = SSVDHelper.loadAndSumUpVectors(sbPath, conf);
Matrix mC = sq.cross(sb);
bbtSquare.assign(mC, Functions.MINUS);
bbtSquare.assign(mC.transpose(), Functions.MINUS);
mC = null;
Matrix outerSq = sq.cross(sq);
outerSq.assign(Functions.mult(xisquaredlen));
bbtSquare.assign(outerSq, Functions.PLUS);