res/values/donottranslate_strings.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  Copyright (C) 2014 The Android Open Source Project

  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.
  -->

<resources>

    <!-- Constant for Euler's number (i.e. "2.7182…"). [CHAR_LIMIT=1] -->
    <string name="const_e">e</string>
    <!-- Constant for pi (i.e. "3.1415…"). [CHAR_LIMIT=1] -->
    <string name="const_pi">π</string>

    <!-- Left parenthesis (e.g. "log(", "2 × (3 - 1)". [CHAR_LIMIT=1] -->
    <string name="lparen">(</string>
    <!-- Right parenthesis (e.g. "log(2)", "(3 - 1) × 2". [CHAR_LIMIT=1] -->
    <string name="rparen">)</string>

    <!-- Addition operator (e.g. "1 + 2"). [CHAR_LIMIT=1] -->
    <string name="op_add">+</string>
    <!-- Divide operator (e.g. "1 ÷ 2"). [CHAR_LIMIT=1] -->
    <string name="op_div">÷</string>
    <!-- Factorial operator (e.g. "2!"). [CHAR_LIMIT=1] -->
    <string name="op_fact">!</string>
    <!-- Multiply operator (e.g. "1 × 2"). [CHAR_LIMIT=1] -->
    <string name="op_mul">×</string>
    <!-- Power operator (e.g. "1 ^ 2"). [CHAR_LIMIT=1] -->
    <string name="op_pow">^</string>
    <!-- Square root operator (e.g. "√1"). [CHAR_LIMIT=1] -->
    <string name="op_sqrt">√</string>
    <!-- Subtraction operator (e.g. "1 - 2"). [CHAR_LIMIT=1] -->
    <string name="op_sub">−</string>

    <!-- Equals operator (e.g. "1 + 2 = ?"). [CHAR_LIMIT=1] -->
    <string name="eq">=</string>
    <!-- Result displayed when expression evaluates to infinity. [CHAR_LIMIT=1] -->
    <string name="inf">∞</string>

</resources>