Error when compiling

[simonhughes22]

I downloaded eigen and specified it's location in the makefile as directed. On Mac OSX, I get the following error when running make from the github folder

~/GitHub/sparse-coding> make
g++ -I /usr/local/include/eigen3 -std=c++11 -O3 -ffast-math sparse.cc utils.cc -o sparse.o -fopenmp
sparse.cc:10:10: fatal error: 'tr1/unordered_map' file not found
#include <tr1/unordered_map>
         ^
1 error generated.
In file included from utils.cc:1:
./utils.h:12:10: fatal error: 'tr1/unordered_map' file not found
#include <tr1/unordered_map>
         ^
1 error generated.
make: *** [make] Error 1