print "sum(yhat == y) * (1.0/len(np.transpose(yhat)))"
    print sum(yhat == y) * (1.0/len(np.transpose(yhat)))

sum(yhat == y) * (1.0/len(np.transpose(yhat)))
[ 0.  0.  0. ...,  0.  0.  0.]

In [80]: sum(yhat == y) * (1.0/len(np.transpose(yhat)))
Out[80]: 0.0426049908703591

In [81]: print "sum(yhat == y) * (1.0/len(np.transpose(yhat)))"
Out[81]: sum(yhat == y) * (1.0/len(np.transpose(yhat)))

In [82]: print sum(yhat == y) * (1.0/len(np.transpose(yhat)))
Out[82]: 0.0426049908704