RefreshRate is an option to Animate and related functions which specifies the refresh rate for frames in animations.
RegionBinarize[image, marker, d] gives a binary version of image that includes the foreground pixels of marker and also connected regions whose pixel values are within a ...
RegionFunction is an option for plotting functions that specifies the region to include in the plot drawn.
RegionPlot3D[pred, {x, x_min, x_max}, {y, y_min, y_max}, {z, z_min, z_max}] makes a plot showing the three-dimensional region in which pred is True.
RegionPlot[pred, {x, x_min, x_max}, {y, y_min, y_max}] makes a plot showing the region in which pred is True.
RegularExpression["regex"] represents the generalized regular expression specified by the string " regex".
Regularization is an option for Sum and Product that specifies what type of regularization to use.
ReleaseHold[expr] removes Hold, HoldForm, HoldPattern, and HoldComplete in expr.
ReliefImage[array] generates a relief image of an array of height values.
ReliefPlot[array] generates a relief plot of an array of height values.