Definition
The indicator function of a subset of a set is a function
defined as
The Iverson bracket allows the equivalent notation, to be used instead of
The function is sometimes denoted or or even just . (The Greek letter χ appears because it is the initial letter of the Greek word characteristic.)
Read more about this topic: Indicator Function
Famous quotes containing the word definition:
“It is very hard to give a just definition of love. The most we can say of it is this: that in the soul, it is a desire to rule; in the spirit, it is a sympathy; and in the body, it is but a hidden and subtle desire to possess—after many mysteries—what one loves.”
—François, Duc De La Rochefoucauld (1613–1680)
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—Ralph Waldo Emerson (1803–1882)
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—Walter Pater (1839–1894)