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/=

/=

type: function (subr)
location: built-in
source file: xlmath.c
Common LISP compatible: yes
supported on: all machines

SYNTAX

(/= <expr1> <expr2> ... )
        <exprN>         -       a numeric expression

DESCRIPTION

The /= (NOT-EQUAL) operation takes an arbitrary number of numeric arguments. It checks to see if all the numeric arguments are different. T is returned if the arguments are numerically not equivalent, NIL is returned otherwise.

EXAMPLES

(/= 1 1)                                ; returns NIL
(/= 1 2)                                ; returns T
(/= 1 1.0)                              ; returns NIL
(/= 1 2 3)                              ; returns T
(/= 1 2 2)                              ; returns NIL
(/= "a" "b")                            ; error: bad argument type
(setq a 1) (setq b 12.4)                ; set up A and B with values
(/= a b)                                ; returns NIL

BUG: The XLISP /= (NOT-EQUAL) function checks to see if the each argument is different from the next in the list. This means that (/= 1 2 3) returns T as it is supposed to, but that (/= 1 2 3 2 1) returns T when it should return NIL. This is only a problem for the /= (NOT-EQUAL) function.


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