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Equal

FilledSmallSquare lhs == rhs returns True if lhs and rhs are identical.

FilledSmallSquare lhs == rhs is used to represent a symbolic equation, to be manipulated using functions like Solve.

FilledSmallSquare lhs == rhs returns True if lhs and rhs are identical expressions.

FilledSmallSquare lhs == rhs returns False if lhs and rhs are determined to be unequal by comparisons between numbers or other raw data, such as strings.

FilledSmallSquare Approximate numbers are considered equal if they differ in at most their last eight binary digits (roughly their last two decimal digits).

FilledSmallSquare 2 == 2. gives True.

FilledSmallSquare == == gives True if all the are equal.

FilledSmallSquare Equal[e] gives True.

FilledSmallSquare For exact numeric quantities, Equal internally uses numerical approximations to establish inequality. This process can be affected by the setting of the global variable $MaxExtraPrecision.

FilledSmallSquare In StandardForm and InputForm, lhs == rhs can be input as lhs \[Equal] rhs or lhs rhs.

FilledSmallSquare It can also be input as lhs \[LongEqual] rhs or lhs rhs.

FilledSmallSquare See Section 1.5.5 and Section 1.5.6.

FilledSmallSquare See also: SameQ, Unequal, KroneckerDelta, Order, Element.

FilledSmallSquare New in Version 1; modified in 4.1.

Further Examples