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Positive

  • Positive[ x ] gives True if x is a positive number.
  • Positive[ x ] gives False if x is manifestly a negative numerical quantity, a complex numerical quantity, or zero. Otherwise, it remains unevaluated.
  • A definition like Positive[ x ] = True effectively specifies that x is a positive number.
  • Definitions for Sign are tested in determining whether linear combinations of expressions are positive.
  • See also: Negative, NonNegative, Sign.

    Further Examples

    Positive is unsure about -x so doesn't evaluate it further.

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