intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 122 insertions, 0 deletions

diff --git a/contrib/python/ipython/py3/IPython/utils/timing.py b/contrib/python/ipython/py3/IPython/utils/timing.py
new file mode 100644
index 0000000000..92f6883c4a
--- /dev/null
+++ b/contrib/python/ipython/py3/IPython/utils/timing.py
@@ -0,0 +1,122 @@
+# encoding: utf-8
+"""
+Utilities for timing code execution.
+"""
+
+#-----------------------------------------------------------------------------
+#  Copyright (C) 2008-2011  The IPython Development Team
+#
+#  Distributed under the terms of the BSD License.  The full license is in
+#  the file COPYING, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+import time
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+# If possible (Unix), use the resource module instead of time.clock()
+try:
+    import resource
+except ImportError:
+    resource = None
+
+# Some implementations (like jyputerlite) don't have getrusage
+if resource is not None and hasattr(resource, "getrusage"):
+    def clocku():
+        """clocku() -> floating point number
+
+        Return the *USER* CPU time in seconds since the start of the process.
+        This is done via a call to resource.getrusage, so it avoids the
+        wraparound problems in time.clock()."""
+
+        return resource.getrusage(resource.RUSAGE_SELF)[0]
+
+    def clocks():
+        """clocks() -> floating point number
+
+        Return the *SYSTEM* CPU time in seconds since the start of the process.
+        This is done via a call to resource.getrusage, so it avoids the
+        wraparound problems in time.clock()."""
+
+        return resource.getrusage(resource.RUSAGE_SELF)[1]
+
+    def clock():
+        """clock() -> floating point number
+
+        Return the *TOTAL USER+SYSTEM* CPU time in seconds since the start of
+        the process.  This is done via a call to resource.getrusage, so it
+        avoids the wraparound problems in time.clock()."""
+
+        u,s = resource.getrusage(resource.RUSAGE_SELF)[:2]
+        return u+s
+
+    def clock2():
+        """clock2() -> (t_user,t_system)
+
+        Similar to clock(), but return a tuple of user/system times."""
+        return resource.getrusage(resource.RUSAGE_SELF)[:2]
+
+else:
+    # There is no distinction of user/system time under windows, so we just use
+    # time.perff_counter() for everything...
+    clocku = clocks = clock = time.perf_counter
+    def clock2():
+        """Under windows, system CPU time can't be measured.
+
+        This just returns perf_counter() and zero."""
+        return time.perf_counter(),0.0
+
+    
+def timings_out(reps,func,*args,**kw):
+    """timings_out(reps,func,*args,**kw) -> (t_total,t_per_call,output)
+
+    Execute a function reps times, return a tuple with the elapsed total
+    CPU time in seconds, the time per call and the function's output.
+
+    Under Unix, the return value is the sum of user+system time consumed by
+    the process, computed via the resource module.  This prevents problems
+    related to the wraparound effect which the time.clock() function has.
+
+    Under Windows the return value is in wall clock seconds. See the
+    documentation for the time module for more details."""
+
+    reps = int(reps)
+    assert reps >=1, 'reps must be >= 1'
+    if reps==1:
+        start = clock()
+        out = func(*args,**kw)
+        tot_time = clock()-start
+    else:
+        rng = range(reps-1) # the last time is executed separately to store output
+        start = clock()
+        for dummy in rng: func(*args,**kw)
+        out = func(*args,**kw)  # one last time
+        tot_time = clock()-start
+    av_time = tot_time / reps
+    return tot_time,av_time,out
+
+
+def timings(reps,func,*args,**kw):
+    """timings(reps,func,*args,**kw) -> (t_total,t_per_call)
+
+    Execute a function reps times, return a tuple with the elapsed total CPU
+    time in seconds and the time per call. These are just the first two values
+    in timings_out()."""
+
+    return timings_out(reps,func,*args,**kw)[0:2]
+
+
+def timing(func,*args,**kw):
+    """timing(func,*args,**kw) -> t_total
+
+    Execute a function once, return the elapsed total CPU time in
+    seconds. This is just the first value in timings_out()."""
+
+    return timings_out(1,func,*args,**kw)[0]
+