cumsum
Cumulative Sums and Products
Description
Returns an vector that is the cumulative sums or
products of all of the elements to that point for each element.
Usage
cumsum(x)
cumprod(x)
Arguments
| x |
a numeric or complex object. Missing values (NAs) are allowed.
|
Details
If the first NA in x is x[j], the j-th
and all following elements of the value are NA.
cumsum and cumprod are members of the Math group
of generic functions.
The cumprod function performs arithmetic in double precision,
even if x has integer storage mode.
- When x is a matrix object, x is converted to a vector
according to column first order.
- When x is a data frame object, the function applies only
on each row.
Value
returns an object like x, whose i-th value is the sum
or product of the first i values in x.
Classes
This function is used as the default method for classes that do not
inherit a specific method for the function or for the Math
group of functions. The result retains the class and the attributes.
If this behavior is not appropriate,
the designer of the class should provide a method
for the function or for the Math group.
See Also
Examples
cumsum(1:6) # returns c(1, 3, 6, 10, 15, 21)
cumprod(1:6) # returns c(1, 2, 6, 24, 120, 720)