In mathematics, the horizontal line test is a test used to determine whether a function is injective (i.e., one-to-one).
Read more about Horizontal Line Test: Horizontal Line Test in Calculus, Horizontal Line Test in Set Theory
Famous quotes containing the words horizontal, line and/or test:
“And yet out of eternity, a thread
separates itself on the blackness,
a horizontal thread
that fumes a little with pallor upon the dark.”
—D.H. (David Herbert)
“The middle years of parenthood are characterized by ambiguity. Our kids are no longer helpless, but neither are they independent. We are still active parents but we have more time now to concentrate on our personal needs. Our children’s world has expanded. It is not enclosed within a kind of magic dotted line drawn by us. Although we are still the most important adults in their lives, we are no longer the only significant adults.”
—Ruth Davidson Bell. Ourselves and Our Children, by Boston Women’s Health Book Collective, ch. 3 (1978)
“A test of what is real is that it is hard and rough. Joys are found in it, not pleasure. What is pleasant belongs to dreams.”
—Simone Weil (1909–1943)