returns True if lhs and rhs are identical.
- lhs==rhs is used to represent a symbolic equation, to be manipulated using functions like Solve.
- lhs==rhs returns True if lhs and rhs are ordinary identical expressions.
- lhs==rhs returns False if lhs and rhs are determined to be unequal by comparisons between numbers or other raw data, such as strings.
- Approximate numbers with machine precision or higher are considered equal if they differ in at most their last seven binary digits (roughly their last two decimal digits).
- For numbers below machine precision the required tolerance is reduced in proportion to the precision of the numbers.
- 2==2. gives True.
- e1==e2==e3 gives True if all the ei are equal.
- Equal[e] gives True.
- 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.
- Equal remains unevaluated when lhs or rhs contains objects such as Indeterminate and Overflow.
- In StandardForm and InputForm, lhs==rhs can be input as lhs\[Equal]rhs or lhsrhs.
- It can also be input as \[LongEqual] or lhsrhs.
- In TraditionalForm, lhs==rhs is output as lhsrhs.
Introduced in 1988
(1.0)| Updated in 2007