=, /=, <, >, <=, >= | Common Lisp Nova Spec

←Apropos →

=, /=, <, >, <=, >=

Function

Syntax

= &rest numbers⁺ → generalized-boolean

/= &rest numbers⁺ → generalized-boolean

< &rest numbers⁺ → generalized-boolean

> &rest numbers⁺ → generalized-boolean

<= &rest numbers⁺ → generalized-boolean

>= &rest numbers⁺ → generalized-boolean

Arguments and Values

number — for <, >, <=, >=: a real; for =, /=: a number.

generalized-boolean — a generalized boolean.

Description

=, /=, <, >, <=, and >= perform arithmetic comparisons on their arguments as follows:

=: The value of = is true if all numbers are the same in value; otherwise it is false. Two complexes are considered equal by = if their real and imaginary parts are equal according to =.
/=: The value of /= is true if no two numbers are the same in value; otherwise it is false.
<: The value of < is true if the numbers are in monotonically increasing order; otherwise it is false.
>: The value of > is true if the numbers are in monotonically decreasing order; otherwise it is false.
<=: The value of <= is true if the numbers are in monotonically nondecreasing order; otherwise it is false.
>=: The value of >= is true if the numbers are in monotonically nonincreasing order; otherwise it is false.

=, /=, <, >, <=, and >= perform necessary type conversions.

Examples

The uses of these functions are illustrated in Figure 12–13.

`(= 3 3)` is true.	`(/= 3 3)` is false.
`(= 3 5)` is false.	`(/= 3 5)` is true.
`(= 3 3 3 3)` is true.	`(/= 3 3 3 3)` is false.
`(= 3 3 5 3)` is false.	`(/= 3 3 5 3)` is false.
`(= 3 6 5 2)` is false.	`(/= 3 6 5 2)` is true.
`(= 3 2 3)` is false.	`(/= 3 2 3)` is false.
`(< 3 5)` is true.	`(<= 3 5)` is true.
`(< 3 -5)` is false.	`(<= 3 -5)` is false.
`(< 3 3)` is false.	`(<= 3 3)` is true.
`(< 0 3 4 6 7)` is true.	`(<= 0 3 4 6 7)` is true.
`(< 0 3 4 4 6)` is false.	`(<= 0 3 4 4 6)` is true.
`(> 4 3)` is true.	`(>= 4 3)` is true.
`(> 4 3 2 1 0)` is true.	`(>= 4 3 2 1 0)` is true.
`(> 4 3 3 2 0)` is false.	`(>= 4 3 3 2 0)` is true.
`(> 4 3 1 2 0)` is false.	`(>= 4 3 1 2 0)` is false.
`(= 3)` is true.	`(/= 3)` is true.
`(< 3)` is true.	`(<= 3)` is true.
`(= 3.0 #c(3.0 0.0))` is true.	`(/= 3.0 #c(3.0 1.0))` is true.
`(= 3 3.0)` is true.	`(= 3.0s0 3.0d0)` is true.
`(= 0.0 -0.0)` is true.	`(= 5/2 2.5)` is true.
`(> 0.0 -0.0)` is false.	`(= 0 -0.0)` is true.
`(<= 0 x 9)` is true if `x` is between `0` and `9`, inclusive
`(< 0.0 x 1.0)` is true if `x` is between `0.0` and `1.0`, exclusive
`(< -1 j (length v))` is true if `j` is a valid array index for a vector `v`

Figure 12–13. Uses of /=, =, <, >, <=, and >=

Exceptional Situations

Might signal type-error if some argument is not a real. Might signal arithmetic-error if otherwise unable to fulfill its contract.

Notes

= differs from eql in that (= 0.0 -0.0) is always true, because = compares the mathematical values of its operands, whereas eql compares the representational values, so to speak.