CVXR (version 1.0)

Logistic-class: The Logistic class.

Description

This class represents the elementwise operation \(\log(1 + e^x)\). This is a special case of log(sum(exp)) that evaluates to a vector rather than to a scalar, which is useful for logistic regression.

Usage

Logistic(x)
# S4 method for Logistic
to_numeric(object, values)
# S4 method for Logistic
sign_from_args(object)
# S4 method for Logistic
is_atom_convex(object)
# S4 method for Logistic
is_atom_concave(object)
# S4 method for Logistic
is_incr(object, idx)
# S4 method for Logistic
is_decr(object, idx)
# S4 method for Logistic
.grad(object, values)

Arguments

x

An '>Expression or numeric constant.

object

A '>Logistic object.

values

A list of numeric values for the arguments

idx

An index into the atom.

Methods (by generic)

• to_numeric: Evaluates e^x elementwise, adds one, and takes the natural logarithm.

• sign_from_args: The atom is positive.

• is_atom_convex: The atom is convex.

• is_atom_concave: The atom is not concave.

• is_incr: The atom is weakly increasing.

• is_decr: The atom is not weakly decreasing.

• .grad: Gives the (sub/super)gradient of the atom w.r.t. each variable

Slots

x

An '>Expression or numeric constant.