NullRecords is an option for Read and related functions which specifies whether null records should be taken to exist between repeated record separators.
OperatingSystem is an option for file and related operations that specifies the type of operating system to use to determine file name and other conventions.
OverBar
(Built-in Mathematica Symbol) OverBar[expr] displays with a bar over expr.
PasteButton[expr] represents a button that pastes expr whenever it is pressed. PasteButton[label, expr] displays with label on the button.
PolarAxes is an option for sector charts and polar plots that specifies whether polar axes should be drawn.
PolynomialExtendedGCD[poly_1, poly_2, x] gives the extended GCD of poly_1 and poly_2 treated as univariate polynomials in x.PolynomialExtendedGCD[poly_1, poly_2, x, Modulus ...
ReflectionTransform[v] gives a TransformationFunction that represents a reflection in a mirror through the origin, normal to the vector v.ReflectionTransform[v, p] gives a ...
Remove
(Built-in Mathematica Symbol) Remove[symbol_1, ...] removes symbols completely, so that their names are no longer recognized by Mathematica. Remove["form_1", "form_2", ...] removes all symbols whose names ...
Resampling is an option that specifies the method to be used for resampling images.
ReturnTextPacket[string] is a MathLink packet containing string, the result of an EnterTextPacket evaluation.