prod_entries function

Product of Entries

The product of entries in a vector or matrix. methods

prod_entries(..., axis = NA_real_, keepdims = FALSE)

## S3 method for class 'Expression'
prod(..., na.rm = FALSE)

Arguments

• ...: Numeric scalar, vector, matrix, or Expression objects.
• axis: (Optional) The dimension across which to apply the function: 1 indicates rows, 2 indicates columns, and NA indicates rows and columns. The default is NA.
• keepdims: (Optional) Should dimensions be maintained when applying the atom along an axis? If FALSE, result will be collapsed into an $n x 1$ column vector. The default is FALSE.
• na.rm: (Unimplemented) A logical value indicating whether missing values should be removed.

Returns

An Expression representing the product of the entries of the input.

Details

This atom is log-log affine, but it is neither convex nor concave.

Examples

n <- 2
X <- Variable(n, n, pos=TRUE)
obj <- sum(X)
constraints <- list(prod_entries(X) == 4)
prob <- Problem(Minimize(obj), constraints)
result <- solve(prob, gp=TRUE)
result$value
result$getValue(X)

n <- 2
X <- Variable(n, n, pos=TRUE)
obj <- sum(X)
constraints <- list(prod(X) == 4)
prob <- Problem(Minimize(obj), constraints)
result <- solve(prob, gp=TRUE)
result$value