ncombinations {arrangements} R Documentation

## Number of combinations

### Description

Number of combinations

### Usage

```ncombinations(x = NULL, k = NULL, n = NULL, v = NULL,
freq = NULL, replace = FALSE, bigz = FALSE)
```

### Arguments

 `x` an integer or a vector, will be treated as `n` if integer; otherwise, will be treated as `v`. Should not be specified together with `n` and `v`. `k` an integer, the number of items drawn, defaults to `n` if `freq` is `NULL` else `sum(freq)` `n` an integer, the total number of items, its value may be implicitly deduced from `length(v)` or `length(freq)` `v` a vector to be drawn, defaults to `1:n`. `freq` an integer vector of item repeat frequencies `replace` an logical to draw items with replacement `bigz` an logical to use gmp::bigz

combinations for generating all combinations and icombinations for iterating combinations

### Examples

```ncombinations(5, 2)
ncombinations(LETTERS, k = 5)

# integer overflow
## Not run: ncombinations(40, 15)
ncombinations(40, 15, bigz = TRUE)

# number of combinations of `c("a", "b", "b")`
# they are `c("a", "b")` and `c("b", "b")`
ncombinations(k = 2, freq = c(1, 2))

# zero sized combinations
ncombinations(5, 0)
ncombinations(5, 6)
ncombinations(0, 1)
ncombinations(0, 0)

```

[Package arrangements version 1.1.9 Index]