cumsum                 package:base                 R Documentation

Cumulative Sums, Products, and Extremes

Description:

     Returns a vector whose elements are the cumulative sums, products,
     minima or maxima of the elements of the argument.

Usage:

     cumsum(x)
     cumprod(x)
     cummax(x)
     cummin(x)

Arguments:

       x: a numeric or complex (not 'cummin' or 'cummax') object, or an
          object that can be coerced to one of these.

Details:

     These are generic functions: methods can be defined for them
     individually or via the 'Math' group generic.

Value:

     A vector of the same length and type as 'x' (after coercion),
     except that 'cumprod' returns a numeric vector for integer input
     (for consistency with '*').  Names are preserved.

     An 'NA' value in 'x' causes the corresponding and following
     elements of the return value to be 'NA', as does integer overflow
     in 'cumsum' (with a warning).

S4 methods:

     'cumsum' and 'cumprod' are S4 generic functions: methods can be
     defined for them individually or via the 'Math' group generic.
     'cummax' and 'cummin' are individually S4 generic functions.

References:

     Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) _The New S
     Language_. Wadsworth & Brooks/Cole. ('cumsum' only.)

Examples:

     cumsum(1:10)
     cumprod(1:10)
     cummin(c(3:1, 2:0, 4:2))
     cummax(c(3:1, 2:0, 4:2))

