rcumsum {FSA} R Documentation

## Computes the prior to or reverse cumulative sum of a vector.

### Description

Computes the prior-to (i.e., the cumulative sum prior to but not including the current value) or the reverse (i.e., the number that large or larger) cumulative sum of a vector. Also works for 1-dimensional tables, matrices, and data.frames, though it is best used with vectors.

### Usage

```rcumsum(x)

pcumsum(x)
```

### Arguments

 `x` a numeric object.

### Value

A numeric vector that contains the prior-to or reverse cumulative sums.

### Note

An `NA` in the vector causes all returned values at and after the first `NA` for `pcumsum` and at and before the last `NA` for `rcumsum` to be `NA`. See the examples.

### Author(s)

Derek H. Ogle, derek@derekogle.com

### See Also

`cumsum`.

### Examples

```## Simple example
cbind(vals=1:10,
cum=cumsum(1:10),
pcum=pcumsum(1:10),
rcum=rcumsum(1:10))

## Example with NA
vals <- c(1,2,NA,3)
cbind(vals,
cum=cumsum(vals),
pcum=pcumsum(vals),
rcum=rcumsum(vals))

## Example with NA
vals <- c(1,2,NA,3,NA,4)
cbind(vals,
cum=cumsum(vals),
pcum=pcumsum(vals),
rcum=rcumsum(vals))

## Example with a matrix
mat <- matrix(c(1,2,3,4,5),nrow=1)
cumsum(mat)
pcumsum(mat)
rcumsum(mat)

## Example with a table (must be 1-d)
df <- sample(1:10,100,replace=TRUE)
tbl <- table(df)
cumsum(tbl)
pcumsum(tbl)
rcumsum(tbl)

## Example with a data.frame (must be 1-d)
df <- sample(1:10,100,replace=TRUE)
tbl <- as.data.frame(table(df))[,-1]
cumsum(tbl)
pcumsum(tbl)
rcumsum(tbl)
```

[Package FSA version 0.8.26.9000 Index]