hstack {CVXR} R Documentation

## Horizontal Concatenation

### Description

The horizontal concatenation of expressions. This is equivalent to `cbind` when applied to objects with the same number of rows.

### Usage

```hstack(...)
```

### Arguments

 `...` Expression objects, vectors, or matrices. All arguments must have the same number of rows.

### Value

An Expression representing the concatenated inputs.

### Examples

```x <- Variable(2)
y <- Variable(3)
c <- matrix(1, nrow = 1, ncol = 5)
prob <- Problem(Minimize(c %*% t(hstack(t(x), t(y)))), list(x == c(1,2), y == c(3,4,5)))
result <- solve(prob)
result\$value

c <- matrix(1, nrow = 1, ncol = 4)
prob <- Problem(Minimize(c %*% t(hstack(t(x), t(x)))), list(x == c(1,2)))
result <- solve(prob)
result\$value

A <- Variable(2,2)
C <- Variable(3,2)
c <- matrix(1, nrow = 2, ncol = 2)
prob <- Problem(Minimize(sum_entries(hstack(t(A), t(C)))), list(A >= 2*c, C == -2))
result <- solve(prob)
result\$value
result\$getValue(A)

D <- Variable(3,3)
expr <- hstack(C, D)
obj <- expr[1,2] + sum(hstack(expr, expr))
constr <- list(C >= 0, D >= 0, D[1,1] == 2, C[1,2] == 3)
prob <- Problem(Minimize(obj), constr)
result <- solve(prob)
result\$value
result\$getValue(C)
result\$getValue(D)
```

[Package CVXR version 1.0-10 Index]