FEAT: Adding timeit function

Author: pavanky

arrayfire/__init__.py

@@ -53,6 +53,7 @@
 from .bcast      import *
 from .index      import *
 from .interop    import *
+from .timer      import *
 
 # do not export default modules as part of arrayfire
 del ct

arrayfire/timer.py

@@ -0,0 +1,51 @@
+#######################################################
+# Copyright (c) 2015, ArrayFire
+# All rights reserved.
+#
+# This file is distributed under 3-clause BSD license.
+# The complete license agreement can be obtained at:
+# http://arrayfire.com/licenses/BSD-3-Clause
+########################################################
+"""
+Functions to time arrayfire functions
+"""
+
+from .library import *
+from .device import (sync, eval)
+from time import time
+
+def timeit(af_func, *args, min_iters = 10):
+    """
+    Function to time arrayfire functions.
+
+    Parameters
+    ----------
+
+    af_func    : arrayfire function
+
+    *args      : arguments to `af_func`
+
+    min_iters  : Minimum number of iterations to be run for `af_func`
+
+    Returns
+    --------
+
+    t   : Time in seconds
+    """
+
+    res = af_func(*args)
+    eval(res)
+    sync()
+
+    start = time()
+    elapsed = 0
+    num_iters = 0
+    while elapsed < 1:
+        for n in range(min_iters):
+            res = af_func(*args)
+            eval(res)
+        sync()
+        elapsed += time() - start
+        num_iters += min_iters
+
+    return elapsed / num_iters