apv: Amalgams Pseudo-Vector Constructor

In trotter: Pseudo-Vectors Containing All Permutations, Combinations and Subsets of Objects Taken from a Vector.

Description

The APV class defines a pseudo-vector containing all the arranged k-amalgams (permutations with replacement) of the objects stored in items. The function apv is a constructor for this class.

Usage

apv(k, items)

Arguments

k	the number of objects taken at a time.
items	a vector of objects to be amalgamated.

Details

The amalgams are arranged according to the order in which the objects appear in items. The arrangement is very similar to that used by the PPV class (see ppv) except that objects are replaced during permutation creation.

Value

an instance of APV.

Author(s)

Richard Ambler

References

Steinhaus-Johnson-Trotter algorithm. (2014, April 29). In Wikipedia, The Free Encyclopedia. Retrieved 13:24, September 5, 2014

See Also

Permutations Pseudo-Vector ppv

Combinations Pseudo-Vector cpv

Selections Pseudo-Vector spv

Subsets Pseudo-Vector sspv

Examples

# create a pseudo-vector of 10-amalgams from the first 15 letters
a <- apv(10, letters[1:15])
# generate a description
print(a)
# compatable with length
length(a)
# inspect a few of the combinations "stored" in a
a[1]
a[1000000]
a[576650390625]

trotter documentation built on May 2, 2019, 1:27 p.m.