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UnitStep

UnitStep[x]
represents the unit step function, equal to 0 for x<0 and 1 for x≥0.
UnitStep[x1, x2, ...]
represents the multidimensional unit step function which is 1 only if none of the x_i are negative.
  • Some transformations are done automatically when UnitStep appears in a product of terms.
  • UnitStep provides a convenient way to represent piecewise continuous functions.
  • For exact numeric quantities, UnitStep internally uses numerical approximations to establish its result. This process can be affected by the setting of the global variable $MaxExtraPrecision.
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