American Foundation for the Blind York City headquarters. Louis Braille was the Frenchman who invented the raised dot code that bears his name. On January 4, 2009, the 200th anniversary of his birth, AFB created an online gallery that includes pictures of him and digitized books and articles. AFB's main headquarters is in Arlington, Virginia. Other offices include New York City; Dallas, Texas; and Huntington, West Virginia. In 2012, AFB added VisionAware to its family of sites in partnership with the "Reader's Digest" Partners for Sight Foundation. The site folded in content from AFB's Senior Site, with new information and resources for adults of all
Dot product representation of a graph Dot product representation of a graph A dot product representation of a simple graph is a method of representing a graph using vector spaces and the dot product from linear algebra. Every graph has a dot product representation. Let "G" be a graph with vertex set "V". Let "F" be a field, and "f" a function from "V" to "F" such that "xy" is an edge of "G" if and only if "f"("x")·"f"("y") ≥ "t". This is the dot product representation of "G". The number "t" is called the dot product threshold, and the smallest possible value of "k" is