Compile fixes for Mac OS X10.9 clang 5.0.0

fixed compile errors on clang 5.0.0
fixed test_akaze_programs.py

Author: oddkiva

src/lib/fed.cpp

@@ -31,6 +31,7 @@
 
 #define _USE_MATH_DEFINES
 #include "fed.h"
+#include <cmath>
 
 using namespace std;
 
@@ -73,7 +74,7 @@ int fed_tau_by_cycle_time(const float& t, const float& tau_max,
   float scale = 0.0;  // Ratio of t we search to maximal t
 
   // Compute necessary number of time steps
-  n = (int)(ceilf(sqrtf(3.0*t/tau_max+0.25f)-0.5f-1.0e-8f)+ 0.5f);
+  n = (int)(ceilf(sqrt(3.0*t/tau_max+0.25f)-0.5f-1.0e-8f)+ 0.5f);
   scale = 3.0*t/(tau_max*(float)(n*(n+1)));
 
   // Call internal FED time step creation routine

test_akaze_programs.py

@@ -15,23 +15,17 @@
 # Helper functions
 def extract_AKAZE_features(imagePath):
   command = " ".join([programs[0], ' -i ', imagePath])
-  p = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-  output, errors = p.communicate()
-  print(output)
+  os.system(command)
 
 def match_AKAZE_features(imagePath1, imagePath2, gdTruthHomography):
   command = " ".join(
     [programs[1], ' -L ', imagePath1, ' -R ', imagePath2, ' -H ', gdTruthHomography] )
-  p = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-  output, errors = p.communicate()
-  print(output)
+  os.system(command)
 
 def compare_AKAZE_BRISK_ORB(imagePath1, imagePath2, gdTruthHomography):
   command = " ".join(
     [programs[2], ' -L ', imagePath1, ' -R ', imagePath2, ' -H ', gdTruthHomography] )
-  p = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-  output, errors = p.communicate()
-  print(output)
+  os.system(command)
 
 # ===============================================================================
 # Example datasets