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    zerop (AutoLISP)

    Verifies that a number evaluates to zero

    Supported Platforms: Windows, Mac OS, and Web

    Signature

    (zerop number)
    number

    Type: Integer or Real

    A numeric value.

    Return Values

    Type: T or nil

    T if number evaluates to zero; otherwise nil.

    Examples

    (zerop 0)
    T
    
    (zerop 0.0)
    T
    
    (zerop 0.0001)
    nil

    Related Concepts

    • Arithmetic Functions Reference (AutoLISP)

    Related Reference

    • numberp (AutoLISP)
    • boundp (AutoLISP)
    • not (AutoLISP)
    • null (AutoLISP)

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