1 files changed, 88 insertions, 0 deletions
diff --git a/yardstick/network_services/helpers/vpp_helpers/receive_rate_interval.py b/yardstick/network_services/helpers/vpp_helpers/receive_rate_interval.py
new file mode 100644
index 000000000..517a99c1f
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+++ b/yardstick/network_services/helpers/vpp_helpers/receive_rate_interval.py
@@ -0,0 +1,88 @@
+# Copyright (c) 2019 Viosoft Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This is a modified copy of
+# https://gerrit.fd.io/r/gitweb?p=csit.git;a=blob_plain;f=resources/libraries/python/MLRsearch/ReceiveRateInterval.py;hb=HEAD
+
+import math
+
+from yardstick.network_services.helpers.vpp_helpers.receive_rate_measurement import \
+    ReceiveRateMeasurement
+
+
+class ReceiveRateInterval(object):
+    """Structure defining two Rr measurements, and their relation."""
+
+    def __init__(self, measured_low, measured_high):
+        """Store the bound measurements after checking argument types.
+
+        :param measured_low: Measurement for the lower bound.
+        :param measured_high: Measurement for the upper bound.
+        :type measured_low: ReceiveRateMeasurement.ReceiveRateMeasurement
+        :type measured_high: ReceiveRateMeasurement.ReceiveRateMeasurement
+        """
+        # TODO: Type checking is not very pythonic,
+        # perhaps users can fix wrong usage without it?
+        if not isinstance(measured_low, ReceiveRateMeasurement):
+            raise TypeError("measured_low is not a ReceiveRateMeasurement: "
+                            "{low!r}".format(low=measured_low))
+        if not isinstance(measured_high, ReceiveRateMeasurement):
+            raise TypeError("measured_high is not a ReceiveRateMeasurement: "
+                            "{high!r}".format(high=measured_high))
+        self.measured_low = measured_low
+        self.measured_high = measured_high
+        # Declare secondary quantities to appease pylint.
+        self.abs_tr_width = None
+        """Absolute width of target transmit rate. Upper minus lower."""
+        self.rel_tr_width = None
+        """Relative width of target transmit rate. Absolute divided by upper."""
+        self.sort()
+
+    def sort(self):
+        """Sort bounds by target Tr, compute secondary quantities."""
+        if self.measured_low.target_tr > self.measured_high.target_tr:
+            self.measured_low, self.measured_high = (
+                self.measured_high, self.measured_low)
+        self.abs_tr_width = (
+                self.measured_high.target_tr - self.measured_low.target_tr)
+        self.rel_tr_width = round(
+            self.abs_tr_width / self.measured_high.target_tr, 5)
+
+    def width_in_goals(self, relative_width_goal):
+        """Return float value.
+
+        Relative width goal is some (negative) value on logarithmic scale.
+        Current relative width is another logarithmic value.
+        Return the latter divided by the former.
+        This is useful when investigating how did surprising widths come to be.
+
+        :param relative_width_goal: Upper bound times this is the goal
+            difference between upper bound and lower bound.
+        :type relative_width_goal: float
+        :returns: Current width as logarithmic multiple of goal width [1].
+        :rtype: float
+        """
+        return round(math.log(1.0 - self.rel_tr_width) / math.log(
+            1.0 - relative_width_goal), 5)
+
+    def __str__(self):
+        """Return string as half-open interval."""
+        return "[{low!s};{high!s})".format(
+            low=self.measured_low, high=self.measured_high)
+
+    def __repr__(self):
+        """Return string evaluable as a constructor call."""
+        return ("ReceiveRateInterval(measured_low={low!r}"
+                ",measured_high={high!r})".format(low=self.measured_low,
+                                                  high=self.measured_high))