cumsum 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  | 
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))
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Licensed under the GNU General Public License.