Functions for getting string array attributes (#88)

* Functions for getting string array attributes

adds get_strattrarray and get_strattrarray!

* Update grb_attrs.jl

* Add files via upload

* Update test_get_strarray.jl

* Update runtests.jl

src/grb_attrs.jl

@@ -133,6 +133,22 @@ function get_charattrarray(model::Model, name::String, start::Integer, len::Inte
     get_charattrarray!(Array{Cchar}(len), model, name, start)
 end
 
+function get_strattrarray(model::Model, name::String, start::Integer, len::Integer)
+    @assert isascii(name)
+    get_strattrarray!(Array(Ptr{UInt8}, len), model, name, start)
+end
+
+function get_strattrarray!(r::Array{Ptr{UInt8}}, model::Model, name::String, start::Integer)
+    @assert isascii(name)
+    ret = @grb_ccall(getstrattrarray, Cint,
+        (Ptr{Void}, Ptr{UInt8}, Cint, Cint, Ptr{Ptr{UInt8}}),
+        model, name, start - 1, length(r), r)
+    if ret != 0
+        throw(GurobiError(model.env, ret))
+    end
+    map(unsafe_string, r)
+end
+
 # setters
 
 function set_intattr!(model::Model, name::String, v::Integer)

test/runtests.jl

@@ -11,7 +11,8 @@ tests = [
     "mathprog",
     "test_grb_attrs",
     "env",
-    "range_constraints"
+    "range_constraints",
+    "test_get_strarray"
 ]
 
 for t in tests

test/test_get_strarray.jl

@@ -0,0 +1,13 @@
+using Gurobi
+using Base.Test
+
+# enviroment and problem
+env = Gurobi.Env()
+m = Gurobi.Model(env, "test")
+
+# read mps problem in Gurobi
+read_model(m, "test_get_strarray.mps")
+
+# test functions
+@test Gurobi.get_strattrarray(m, "VarName", 1, Gurobi.num_vars(m)) == ["XONE","YTWO","ZTHREE"]
+@test Gurobi.get_strattrarray(m, "ConstrName", 1, Gurobi.num_constrs(m)) == ["LIM1","LIM2","MYEQN"]

test/test_get_strarray.mps

@@ -0,0 +1,22 @@
+*Source: http://lpsolve.sourceforge.net/5.5/mps-format.htm
+NAME          TESTPROB
+ROWS
+ N  COST
+ L  LIM1
+ G  LIM2
+ E  MYEQN
+COLUMNS
+    XONE      COST                 1   LIM1                 1
+    XONE      LIM2                 1
+    YTWO      COST                 4   LIM1                 1
+    YTWO      MYEQN               -1
+    ZTHREE    COST                 9   LIM2                 1
+    ZTHREE    MYEQN                1
+RHS
+    RHS1      LIM1                 5   LIM2                10
+    RHS1      MYEQN                7
+BOUNDS
+ UP BND1      XONE                 4
+ LO BND1      YTWO                -1
+ UP BND1      YTWO                 1
+ENDATA