ammend install instructions and check for env-var to link against cud…

…a libs

BUILD.md

@@ -24,6 +24,7 @@ $ git clone --recurse-submodules https://github.com/rapidsai/cuml.git
 $ cd cuML
 $ mkdir build
 $ cd build
+$ export CUDA_BIN_PATH=$CUDA_HOME # (optional CUDA_HOME=/path/to/cuda/)
 $ cmake ..
 ```
 
@@ -39,7 +40,7 @@ Cannot generate a safe runtime search path for target ml_test because files
 in some directories may conflict with libraries in implicit directories:
 ```
 
-The configuration script will print the BLAS found on the search path. If the version found does not match the version intended, use the flag `-DBLAS_LIBRARIES=/path/to/blas.so` with the `cmake` command to force your own version. 
+The configuration script will print the BLAS found on the search path. If the version found does not match the version intended, use the flag `-DBLAS_LIBRARIES=/path/to/blas.so` with the `cmake` command to force your own version.
 
 
 3. Build `libcuml`:

python/setup.py

@@ -19,6 +19,7 @@
 from Cython.Build import cythonize
 import versioneer
 from distutils.sysconfig import get_python_lib
+import os
 
 
 install_requires = [
@@ -28,6 +29,11 @@
 
 cython_files = ['cuML/cuml.pyx']
 
+cuda_lib_dir = '/usr/local/cuda/include'
+
+if os.environ.get('CUDA_HOME', False):
+    cuda_lib_dir = os.path.join(os.environ.get('CUDA_HOME'), 'include')
+
 extensions = [
     Extension("cuml",
               sources=cython_files,
@@ -37,7 +43,7 @@
                             '../cuML/external/ml-prims/external/cutlass',
                             '../cuML/external/cutlass',
                             '../cuML/external/ml-prims/external/cub',
-                            '/usr/local/cuda/include'],
+                            cuda_lib_dir],
               library_dirs=[get_python_lib()],
               libraries=['cuda', 'cuml'],
               language='c++',