get float value from Mat

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I have a matrix of size [2 x 2], of type 64FC1, named eigenvectors.

[0.707152069011339, 0.7070614904610364;
 -0.7070614904610364, 0.707152069011339]

If I write cout<<(float)eigenvectors.at<float>(0,0); or cout<<eigenvectors.at<float>(0,0); I get number 5.25957e+19 instead of 0.707152069011339. How can I get exactly number 0.707152069011339 or any of numbers of this matrix?