added dot

Author: nantonel

docs/src/functions.md

@@ -12,7 +12,7 @@ huberloss
 sqrhingeloss
 crossentropy
 logisticloss
-logbarrier
+dot
 ```
 
 ## Nonsmooth functions
@@ -22,6 +22,7 @@ norm
 maximum
 sumpositive
 hingeloss
+logbarrier
 ```
 
 ## Inequality constraints

src/syntax/terms/proximalOperators_bind.jl

@@ -207,6 +207,20 @@ f(\\mathbf{x}) = \\sum_i \\max \\{x_i, 0\\}.
 sumpositive(ex::AbstractExpression) =
 Term(SumPositive(), ex)
 
+import Base: dot
+
+"""
+`dot(c::AbstractVector, x::AbstractExpression)`
+
+Applies the function: 
+```math
+f(\\mathbf{x}) = \\mathbf{c}^{T}\\mathbf{x}.
+```
+"""
+dot(c::AbstractVector, ex::AbstractExpression) =
+Term(Linear(c), ex)
+
+
 # Inequalities
 
 import Base: <=

test/test_terms.jl

@@ -150,6 +150,11 @@ cf = huberloss(x,a)
 @test cf.lambda == 1
 @test cf.f(~x) == (HuberLoss(a))(~x)
 
+a = randn(size(x))
+cf = dot(a,x)
+@test cf.lambda == 1
+@test cf.f(~x) == (Linear(a))(~x)
+
 #IndBinary
 lu = (-1,randn(length(~x)))
 cf = x == lu