R: Add Column

add.column {lpSolveAPI} | R Documentation

## Add Column

### Description

Add a column to an lpSolve linear program model object.

### Usage

    add.column(lprec, x, indices)

### Arguments

`lprec` | an lpSolve linear program model object.
`x` | a numeric vector containing the elements (only the nonzero elements if the `indices` argument is also provided) of the column to be added. The length of `x` must be equal to the number of constraints in `lprec` unless `indices` is provided.
`indices` | optional for sparse `x`. A numeric vector the same length as `x` of unique values from the set {0, ..., m} where m is the number of constraints in `lprec`; `x[i]` is entered into constraint `indices[i]` in the added column. The coefficients for the constraints not in `indices` are set to zero. In particular, index `0` is the objective function coefficient in the added column and is set to zero by default. This argument should be omitted when `length(x) == m`.

### Details

This function adds an additional column to an lpSolve linear program model object. If multiple columns are to be added, performance can be improved by calling `resize.lp` before adding the columns.

### Value

a `NULL` value is invisibly returned.

### Author(s)

Kjell Konis kjell.konis@me.com

### References

http://lpsolve.sourceforge.net/5.5/index.htm

### See Also

`resize.lp`

### Examples

    lps.model <- make.lp(4, 0)
    add.column(lps.model, c(6,2,4,9))
    add.column(lps.model, c(3,1,5), indices = c(1,2,4))

[Package lpSolveAPI version 5.5.2.0-17 Index]