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)
“every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view.”
—Thomas Nagel (b. 1938)