Handle dependency of numpy during setup

setup.py

@@ -2,14 +2,16 @@
 import sys
 import re
 from setuptools import setup, Extension
+from setuptools.command.build_ext import build_ext as _build_ext
 
 #Test if numpy is installed
-try:
-	import numpy as np
-except:
-	sys.exit("ERROR: Numpy needed for TOBIAS installation. Numpy can be installed using the command \"pip install numpy\"")
-
-cmdclass = {}
+class build_ext(_build_ext):
+    def finalize_options(self):
+        _build_ext.finalize_options(self)
+        # Prevent numpy from thinking it is still in its setup process:
+        __builtins__.__NUMPY_SETUP__ = False
+        import numpy as np
+       	self.include_dirs.append(np.get_include())
 
 #Add cython modules depending on the availability of cython
 try:
@@ -20,15 +22,17 @@
 	use_cython = True
 
 if use_cython:
-	ext_modules = [Extension("tobias.utils.ngs", ["tobias/utils/ngs.pyx"], include_dirs=[np.get_include()]),
-					Extension("tobias.utils.sequences", ["tobias/utils/sequences.pyx"], include_dirs=[np.get_include()]),
-					Extension("tobias.utils.signals", ["tobias/utils/signals.pyx"], include_dirs=[np.get_include()])]
-	cmdclass.update({'build_ext': build_ext})
+	ext_modules = [Extension("tobias.utils.ngs", ["tobias/utils/ngs.pyx"]), #, include_dirs=[np.get_include()]),
+					Extension("tobias.utils.sequences", ["tobias/utils/sequences.pyx"]), #include_dirs=[np.get_include()]),
+					Extension("tobias.utils.signals", ["tobias/utils/signals.pyx"])] #, include_dirs=[np.get_include()])]
+	#cmdclass.update({'build_ext': build_ext})
 
 else:
-	ext_modules = [Extension("tobias.utils.ngs", ["tobias/utils/ngs.c"], include_dirs=[np.get_include()]),
-						Extension("tobias.utils.sequences", ["tobias/utils/sequences.c"], include_dirs=[np.get_include()]),
-						Extension("tobias.utils.signals", ["tobias/utils/signals.c"], include_dirs=[np.get_include()])]
+	ext_modules = [Extension("tobias.utils.ngs", ["tobias/utils/ngs.c"]), #, include_dirs=[np.get_include()]),
+						Extension("tobias.utils.sequences", ["tobias/utils/sequences.c"]), #, include_dirs=[np.get_include()]),
+						Extension("tobias.utils.signals", ["tobias/utils/signals.c"])] #, include_dirs=[np.get_include()])]
+
+cmdclass = {'build_ext': build_ext}
 
 #Path of setup file to establish version
 setupdir = os.path.abspath(os.path.dirname(__file__))
@@ -59,6 +63,7 @@ def readme():
 		},
 		ext_modules=ext_modules,
 		cmdclass = cmdclass,
+		setup_requires=["numpy"],
 		#dependency_links=['https://github.com/jhkorhonen/MOODS/releases/download/v1.9.3/MOODS-python-1.9.3.tar.gz#egg=MOODS-python-1.9.3'],	
 		install_requires=[
 			'numpy',