Critical Points and Discriminant
If the gradient of f (i.e. its derivative in the vector sense) is zero at some point x, then f has a critical point (or stationary point) at x. The determinant of the Hessian at x is then called the discriminant. If this determinant is zero then x is called a degenerate critical point of f, this is also called a non-Morse critical point of f. Otherwise it is non-degenerate, this is called a Morse critical point of f.
Read more about this topic: Hessian Matrix
Famous quotes containing the words critical and/or points:
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—Wyndham Lewis (1882–1957)
“Mankind is not a circle with a single center but an ellipse with two focal points of which facts are one and ideas the other.”
—Victor Hugo (1802–1885)