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diff --git a/ethosu/vela/numeric_util.py b/ethosu/vela/numeric_util.py
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+# Copyright (C) 2020 Arm Limited or its affiliates. All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# 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
+#
+# 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.
+
+
+# Description:
+# Numerical utilities for various types of rounding etc.
+
+import math
+import numpy as np
+
+
+def round_up(a, b):
+    return ((a + b - 1) // b) * b
+
+
+def round_up_divide(a, b):
+    return (a + b - 1) // b
+
+
+def round_up_to_int(v):
+    return int(math.ceil(v))
+
+
+def round_down_to_power_of_two(v):
+    assert v > 0
+    while v & (v - 1):
+        v &= v - 1
+
+    return v
+
+
+def round_up_to_power_of_two(v):
+    return round_down_to_power_of_two(2 * v - 1)
+
+
+def round_down_log2(v):
+    return int(math.floor(np.log2(v)))
+
+
+def round_up_log2(v):
+    return int(math.ceil(np.log2(v)))
+
+
+def round_to_int(v):
+    return np.rint(v).astype(np.int64)
+
+
+# Performs rounding away from zero.
+# n.b. This is identical to C++11 std::round()
+def round_away_zero(f):
+    r = -0.5 if (f < 0) else 0.5
+    return np.trunc(f + r)
+
+
+def quantise_float32(f, scale=1.0, zero_point=0):
+    return zero_point + int(round_away_zero(np.float32(f) / np.float32(scale)))
+
+
+def clamp_tanh(x):
+    if x <= -4:
+        y = -1.0
+    elif x >= 4:
+        y = 1.0
+    else:
+        y = math.tanh(x)
+    return y
+
+
+def clamp_sigmoid(x):
+    if x <= -8:
+        y = 0.0
+    elif x >= 8:
+        y = 1.0
+    else:
+        y = 1 / (1 + math.exp(-x))
+    return y