def binfo(basis):
 A=[list(c['cov']) for c in basis]
 Mx=[list(r) for r in zip(*A)]
 I=inv(Mx)
 x=[sum(I[i][j] for j in range(7)) for i in range(7)]
 cb=[c['cost'] for c in basis]
 pi=[sum(I[j][i]*cb[j] for j in range(7)) for i in range(7)]
 return I,x,pi