Unary function

A unary function is a function that takes one argument. A unary operator belongs to a subset of unary functions, in that its range coincides with its domain.

Example : $a{\mathrel {+{+}}}$
here $a$ is an operand which is operated on by a unary operator in postfix notation, denoted by ${\mathrel {+{+}}}$, with the general meaning in computer science of

$a:=a+1$,

in mathematical notation

${\mathrel {+{+}}}:\;a\mapsto a+1.$

Many of the elementary functions are unary functions, in particular the trigonometric functions, logarithm with a pre-specified base, exponentiation to a pre-specified power or of a pre-specified base, and hyperbolic functions are unary.

See also

• Arity
• Binary function
• Binary operator
• List of mathematical functions
• Ternary operation
• Unary operation

References

• Foundations of Genetic Programming