R: Generate sparse constraint matrix for 8-queens problem

make.q8 {lpSolve} | R Documentation

## Generate sparse constraint matrix for 8-queens problem

### Description

Generate sparse constraint matrix for 8-queens problem

### Usage

     make.q8 ()

### Arguments

None.

### Details

Sparse constraints come in a three-column matrix or data frame. Each row gives the row number, column number, and value of a particular non-zero entry in the constraint matrix. This function produces the sparse constraint matrix for the 8-queens problem (in which the object is to place eight queens on a chessboard with no two sharing a row, column or diagonal). The resulting sparse representation is 252 x 3, compared to 42 x 64 for the usual representation.

### Value

A 252 x 3 numeric matrix. See lp for the complete example.

### Author(s)

Sam Buttrey, buttrey@nps.edu

### See Also

`lp`

[Package lpSolve version 5.6.13 Index]