SWI-Prolog -- (=\=)/2

Documentation
- Reference manual
  - Built-in Predicates
    - Arithmetic
      - General purpose arithmetic
        
        >/2
        
        </2
        
        =</2
        
        >=/2
        
        =\=/2
        
        =:=/2
        
        is/2
        
        Arithmetic types
        
        Rational number examples
        
        Rational numbers or floats
        
        IEEE 754 floating point arithmetic
        
        Floating point arithmetic precision
        
        Arithmetic Functions
- Packages

Availability:built-in

[ISO]+Expr1 =\= +Expr2

True if expression Expr1 evaluates to a number non-equal to Expr2.