Wolfram Language & System 10.4 (2016)|Legacy Documentation

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gives , , or depending on whether x is negative, zero, or positive.


  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • For nonzero complex numbers z, Sign[z] is defined as z/Abs[z].
  • Sign tries various transformations in trying to determine the sign of symbolic expressions.
  • For exact numeric quantities, Sign internally uses numerical approximations to establish its result. This process can be affected by the setting of the global variable $MaxExtraPrecision.
  • Sign automatically threads over lists.
Introduced in 1988
| Updated in 1996