| # Copyright 2018 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| """Utility functions for processing floating point operations.""" |
| |
| ABSOLUTE_TOLERANCE = 0.000001 |
| |
| |
| def AlmostEquals(float_a, float_b, tolerance=ABSOLUTE_TOLERANCE): |
| """Determines whether two floating points are very close to one another. |
| |
| Args: |
| float_a (float): The first number to compare. |
| float_b (float): The second number to compare. |
| tolerance (float): The maximum allowalbe distance between the two numbers. |
| |
| Returns: |
| (bool): Whether or not the two input floating points are almost equal within |
| the specified tolerance. |
| """ |
| assert float_a is not None |
| assert float_b is not None |
| |
| # Add support for ints too. |
| float_a = float(float_a) |
| float_b = float(float_b) |
| |
| if not float_a or not float_b: |
| return abs(float_a - float_b) <= tolerance |
| |
| percentage_same = ( |
| min(abs(float_a), abs(float_b)) / max(abs(float_a), abs(float_b))) |
| |
| import numpy # workaround to run locally. |
| |
| return (numpy.sign(float_a) == numpy.sign(float_b) and |
| 1.0 - percentage_same <= tolerance) |
