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:
“The male has been persuaded to assume a certain onerous and disagreeable rôle with the promise of rewards—material and psychological. Women may in the first place even have put it into his head. BE A MAN! may have been, metaphorically, what Eve uttered at the critical moment in the Garden of Eden.”
—Wyndham Lewis (1882–1957)
“A bath and a tenderloin steak. Those are the high points of a man’s life.”
—Curtis Siodmak (1902–1988)