+++ /dev/null
-
-/*******************************************************************************
-
- Copyright (c) 2009, Charles McGarvey
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
-
- * Redistributions of source code must retain the above copyright notice,
- this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above copyright notice,
- this list of conditions and the following disclaimer in the documentation
- and/or other materials provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
- FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-*******************************************************************************/
-
-#include <cstdlib> // srand, rand, RAND_MAX
-#include <ctime> // time
-#include <cmath> // log
-#include <climits> // ULONG_MAX
-
-#include "random.hh"
-
-
-namespace rng {
-
-unsigned seed(unsigned theSeed)
-{
- srand(theSeed);
- return theSeed;
-}
-
-unsigned seed()
-{
- return seed(time(0));
-}
-
-
-template <typename T>
-T get()
-{
- const float ln2 = 0.693147;
- static const unsigned bitsPerPiece = std::log(float(RAND_MAX)) / ln2;
- static const unsigned sizeOfType = sizeof(T) * 8;
- static const unsigned pieces = sizeOfType / bitsPerPiece +
- ((sizeOfType % bitsPerPiece) ? 1 : 0);
-
- T bits = 0;
-
- // we need to call rand() multiple times if it won't provide enough random
- // bits to fill the size of the given type
- for (unsigned i = 0; i < pieces; i++)
- {
- long piece = rand();
- bits |= piece << (i * bitsPerPiece);
- }
-
- return bits;
-}
-
-
-template <>
-bool get<bool>()
-{
- return rand() % 2;
-}
-
-template <typename T>
-T get(T lower, T upper)
-{
- unsigned short randInt = get<unsigned int>();
- return lower + T(randInt % (upper - lower + 1));
-}
-
-template <>
-float get(float lower, float upper)
-{
- unsigned long randInt = get<unsigned long>();
- return (float(randInt) / float(ULONG_MAX)) * (upper - lower) + lower;
-}
-
-template <>
-double get(double lower, double upper)
-{
- unsigned long long randInt = get<unsigned long long>();
- return (double(randInt) / double(ULLONG_MAX)) * (upper - lower) + lower;
-}
-
-template <>
-float get()
-{
- return get<float>(0.0, 1.0);
-}
-
-template <>
-double get()
-{
- return get<double>(0.0, 1.0);
-}
-
-
-}; // namespace rng
-
-/** vim: set ts=4 sw=4 tw=80: *************************************************/
-