From f8abe8974ac5f49ab6282c4584899333dd9611a6 Mon Sep 17 00:00:00 2001 From: Yann Duplouy Date: Wed, 20 Nov 2019 11:25:16 +0100 Subject: [PATCH] Modifying how uniform integer are generated --- src/xbt/random.cpp | 16 ++-------------- src/xbt/random_test.cpp | 2 +- 2 files changed, 3 insertions(+), 15 deletions(-) diff --git a/src/xbt/random.cpp b/src/xbt/random.cpp index 70456494aa..449782a4f6 100644 --- a/src/xbt/random.cpp +++ b/src/xbt/random.cpp @@ -39,24 +39,12 @@ int uniform_int(int min, int max) int xbt_uniform_int(int min, int max) { - unsigned long gmin = mt19937_gen.min(); - unsigned long gmax = mt19937_gen.max(); - unsigned long grange = gmax - gmin + 1; unsigned long range = max - min + 1; + xbt_assert(range > 0, "Overflow in the uniform integer distribution, please use a smaller range."); xbt_assert( min <= max, "The maximum value for the uniform integer distribution must be greater than or equal to the minimum value"); - xbt_assert(range <= grange, "The current implementation of the uniform integer distribution does not allow range to " - "be higher than mt19937's range"); - unsigned long mult = grange / range; - unsigned long maxallowed = gmin + (mult + 1) * range - 1; - while (true) { - unsigned long value = mt19937_gen(); - if (value > maxallowed) { - } else { - return value % range + min; - } - } + return min + (int)(range * xbt_uniform_real(0, 1)); } double uniform_real(double min, double max) diff --git a/src/xbt/random_test.cpp b/src/xbt/random_test.cpp index c93049b8b0..faffe9d721 100644 --- a/src/xbt/random_test.cpp +++ b/src/xbt/random_test.cpp @@ -14,7 +14,7 @@ TEST_CASE("xbt::random: Random Number Generation") simgrid::xbt::random::set_mersenne_seed(12345); REQUIRE(simgrid::xbt::random::exponential(25) == 0.00291934351538427348); - REQUIRE(simgrid::xbt::random::uniform_int(1, 6) == 4); + REQUIRE(simgrid::xbt::random::uniform_int(1, 6) == 6); REQUIRE(simgrid::xbt::random::uniform_real(0, 1) == 0.31637556043369124970); REQUIRE(simgrid::xbt::random::normal(0, 2) == 1.62746784745133976635); } -- 2.20.1