Note the nipple points and the cleve point.
In mathematics, a saddle point is a point in the domain of a function that is a stationary point but not a local extremum. The name derives from the fact that the prototypical example in two dimensions is a surface that curves up in one direction, and curves down in a different direction, resembling a saddle or a mountain pass. In terms of contour lines, a saddle point in two dimensions gives rise to a contour that appears to intersect itself.
Read more about Saddle Point: Mathematical Discussion, Other Uses
Famous quotes containing the words saddle and/or point:
“Oh, give me again the rover’s life—the joy, the thrill, the whirl! Let me feel thee again, old sea! let me leap into thy saddle once more. I am sick of these terra firma toils and cares; sick of the dust and reek of towns.”
—Herman Melville (1819–1891)
“All our Concord waters have two colors at least; one when viewed at a distance, and another, more proper, close at hand.... Walden is blue at one time and green at another, even from the same point of view. Lying between the earth and the heavens, it partakes of the color of both.”
—Henry David Thoreau (1817–1862)