makeH {rcdd} R Documentation

## make H-representation of convex polyhedron

### Description

Construct H-representation of convex polyhedron, set of points `x` satisfying

```    a1 %*% x <= b1
a2 %*% x == b2
```
see `scdd` for description of valid representations.

### Usage

```makeH(a1, b1, a2, b2, x = NULL)
addHeq(a, b, x)
addHin(a, b, x)
```

### Arguments

 `a1` numerical matrix for inequality constraints. If vector, treated as matrix with one row. `b1` numerical right hand side vector for inequality constraints. `a2` numerical matrix for equality constraints. If vector, treated as matrix with one row. `b2` numerical right hand side vector for equality constraints. `x` if not `NULL`, a valid H-representation. `a` numerical matrix for constraints. If vector, treated as matrix with one row. Constraints are equality in `addHeq` and inequality in `addHin`. `b` numerical right hand side vector for constraints.

Arguments `a1`, `b1`, `a2`, and `b2` may be missing, but must be missing in pairs. Rows in `x`, if any, are added to new rows corresponding to the constraints given by the other arguments.

### Value

a cdd object that can be handed to `scdd`.

### See Also

`scdd`, `validcdd`

### Examples

```d <- 4
# unit simplex in H-representation
qux <- makeH(- diag(d), rep(0, d), rep(1, d), 1)
print(qux)
# add an inequality constraint
qux <- addHin(c(1, -1, 0, 0), 0, qux)
print(qux)
# drop a constraint
qux <- qux[- 3, ]
print(qux)
```

[Package rcdd version 1.1 Index]