Declare decision variables

num_var declares a continuous variable, int_var an integer one, and bin_var a binary one. With n greater than 1 the declaration is a vector variable: x[3] indexes it, sum(x) folds it, arithmetic is elementwise, and per-element bounds are given as vectors of length n. Solutions come back keyed "x" for a scalar and "x[1]", "x[2]", ... for a vector.

Usage

num_var(m, name, lower = -Inf, upper = Inf, n = 1, start = 0)

int_var(m, name, lower = -Inf, upper = Inf, n = 1, start = 0)

bin_var(m, name, n = 1)

add_var(
  m,
  name,
  lower = -Inf,
  upper = Inf,
  n = 1,
  start = 0,
  domain = c("num", "int", "bin")
)

Arguments

m

A model().

name

The variable's name, unique within the model.

lower, upper

Bounds; -Inf / Inf leave a direction unbounded. A vector of length n sets per-element bounds.

n

How many elements the variable has.

start

The initial point handed to the solver.

domain

For add_var: "num", "int" or "bin".

Value

The variable handle (an expression of length n).

add_var returns the model, invisibly.

Details

The handle is returned and is also retrievable from the model as m$x; the add_var variant returns the model instead, for pipes.