aboutsummaryrefslogtreecommitdiffstats
path: root/guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java
diff options
context:
space:
mode:
Diffstat (limited to 'guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java')
-rw-r--r--guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java119
1 files changed, 0 insertions, 119 deletions
diff --git a/guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java b/guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java
deleted file mode 100644
index 71095e5..0000000
--- a/guava-tests/benchmark/com/google/common/math/BigIntegerMathBenchmark.java
+++ /dev/null
@@ -1,119 +0,0 @@
-/*
- * Copyright (C) 2011 The Guava Authors
- *
- * 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.
- */
-
-package com.google.common.math;
-
-import static com.google.common.math.MathBenchmarking.ARRAY_MASK;
-import static com.google.common.math.MathBenchmarking.ARRAY_SIZE;
-import static com.google.common.math.MathBenchmarking.RANDOM_SOURCE;
-import static java.math.RoundingMode.CEILING;
-
-import com.google.caliper.Param;
-import com.google.caliper.Runner;
-import com.google.caliper.SimpleBenchmark;
-import com.google.common.math.BigIntegerMath;
-import com.google.common.math.IntMath;
-import com.google.common.math.LongMath;
-
-import java.math.BigInteger;
-
-/**
- * Benchmarks for the non-rounding methods of {@code BigIntegerMath}.
- *
- * @author Louis Wasserman
- */
-public class BigIntegerMathBenchmark extends SimpleBenchmark {
- private static final int[] factorials = new int[ARRAY_SIZE];
- private static final int[] slowFactorials = new int[ARRAY_SIZE];
- private static final int[] binomials = new int[ARRAY_SIZE];
-
- @Param({"50", "1000", "10000"})
- int factorialBound;
-
- @Override
- protected void setUp() {
- for (int i = 0; i < ARRAY_SIZE; i++) {
- factorials[i] = RANDOM_SOURCE.nextInt(factorialBound);
- slowFactorials[i] = RANDOM_SOURCE.nextInt(factorialBound);
- binomials[i] = RANDOM_SOURCE.nextInt(factorials[i] + 1);
- }
- }
-
- /**
- * Previous version of BigIntegerMath.factorial, kept for timing purposes.
- */
- private static BigInteger slowFactorial(int n) {
- if (n <= 20) {
- return BigInteger.valueOf(LongMath.factorial(n));
- } else {
- int k = 20;
- return BigInteger.valueOf(LongMath.factorial(k)).multiply(slowFactorial(k, n));
- }
- }
-
- /**
- * Returns the product of {@code n1} exclusive through {@code n2} inclusive.
- */
- private static BigInteger slowFactorial(int n1, int n2) {
- assert n1 <= n2;
- if (IntMath.log2(n2, CEILING) * (n2 - n1) < Long.SIZE - 1) {
- // the result will definitely fit into a long
- long result = 1;
- for (int i = n1 + 1; i <= n2; i++) {
- result *= i;
- }
- return BigInteger.valueOf(result);
- }
-
- /*
- * We want each multiplication to have both sides with approximately the same number of digits.
- * Currently, we just divide the range in half.
- */
- int mid = (n1 + n2) >>> 1;
- return slowFactorial(n1, mid).multiply(slowFactorial(mid, n2));
- }
-
- public int timeSlowFactorial(int reps) {
- int tmp = 0;
- for (int i = 0; i < reps; i++) {
- int j = i & ARRAY_MASK;
- tmp += slowFactorial(slowFactorials[j]).intValue();
- }
- return tmp;
- }
-
- public int timeFactorial(int reps) {
- int tmp = 0;
- for (int i = 0; i < reps; i++) {
- int j = i & ARRAY_MASK;
- tmp += BigIntegerMath.factorial(factorials[j]).intValue();
- }
- return tmp;
- }
-
- public int timeBinomial(int reps) {
- int tmp = 0;
- for (int i = 0; i < reps; i++) {
- int j = i & 0xffff;
- tmp += BigIntegerMath.binomial(factorials[j], binomials[j]).intValue();
- }
- return tmp;
- }
-
- public static void main(String[] args) {
- Runner.main(BigIntegerMathBenchmark.class, args);
- }
-}