| cumsum {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 |
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).
In the complex case with NAs, these NA elements may
have finite real or imaginary parts, notably for cumsum(),
fulfilling the identity Im(cumsum(x)) \equiv cumsum(Im(x)).
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))