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)
“When our relatives are at home, we have to think of all their good points or it would be impossible to endure them. But when they are away, we console ourselves for their absence by dwelling on their vices.”
—George Bernard Shaw (1856–1950)