From 850eedee7a19882165c7d43a906329254d5b45bf Mon Sep 17 00:00:00 2001
From: schillic <schillic@informatik.uni-freiburg.de>
Date: Mon, 29 Jan 2018 20:30:19 +0100
Subject: [PATCH] fix scalar multiplication of a LinearMap

---
 src/LinearMap.jl       | 26 +++++++++++++++++++++++---
 test/unit_LinearMap.jl |  2 ++
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/LinearMap.jl b/src/LinearMap.jl
index 4b6a2809a9..10c3963bd4 100644
--- a/src/LinearMap.jl
+++ b/src/LinearMap.jl
@@ -23,7 +23,7 @@ LinearMap(M::AbstractMatrix{N}, map::LinearMap{N, S}
 
 """
 ```
-    *(M::AbstractMatrix{<:Real}, S::LazySet)
+    *(M::AbstractMatrix{<:Real}, X::LazySet)
 ```
 
 Return the linear map of a convex set.
@@ -31,7 +31,7 @@ Return the linear map of a convex set.
 ### Input
 
 - `M` -- matrix/linear map
-- `S` -- convex set
+- `X` -- convex set
 
 ### Output
 
@@ -56,7 +56,7 @@ Return a linear map of a convex set by a scalar value.
 ### Input
 
 - `a` -- real scalar
-- `S` -- convex set
+- `X` -- convex set
 
 ### Output
 
@@ -66,6 +66,26 @@ function *(a::N, X::S)::LinearMap{N, S} where {S<:LazySet{N}} where {N<:Real}
     return LinearMap(a * speye(N, dim(X)), X)
 end
 
+"""
+```
+    *(a::N, map::S)::S where {S<:LinearMap{N, S}} where {N<:Real}
+```
+
+Return a linear map scaled by a scalar value.
+
+### Input
+
+- `a` -- real scalar
+- `map` -- linear map
+
+### Output
+
+The scaled linear map.
+"""
+function *(a::N, map::S)::S where {S<:LinearMap{N, T}} where {N<:Real} where {T}
+    return LinearMap(a * map.M, map.sf)
+end
+
 """
 ```
     *(M::AbstractMatrix, Z::ZeroSet)
diff --git a/test/unit_LinearMap.jl b/test/unit_LinearMap.jl
index c14611f290..f12b3a8d59 100644
--- a/test/unit_LinearMap.jl
+++ b/test/unit_LinearMap.jl
@@ -33,6 +33,8 @@ for N in [Float64, Rational{Int}, Float32]
     # scalar multiplication
     b = BallInf(N[0., 0.], N(1.))
     lm = N(2.) * b
+    # repeated scalar multiplication
+    lm2 = N(2.) * lm
     # Test Dimension
     @test dim(lm) == 2
     # Test Support Vector