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lumiera_/tests/library/random-draw-test.cpp
Ichthyostega 229541859d Chain-Load: demonstrate use of reduction rule 
... special rule to generate a fixed expansion on each seed
... consecutive reductions join everything back into one chain
... can counterbalance expansions and reductions
2023-11-30 03:20:23 +01:00

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/*
RandomDraw(Test) - verify the component builder for random selected values
Copyright (C) Lumiera.org
2023, Hermann Vosseler <Ichthyostega@web.de>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
* *****************************************************/
/** @file random-draw-test.cpp
** unit test \ref RandomDraw_test
*/
#include "lib/test/run.hpp"
#include "lib/random-draw.hpp"
#include "lib/format-string.hpp"
#include "lib/test/test-helper.hpp"
#include <array>
namespace lib {
namespace test{
using util::_Fmt;
using lib::meta::_FunRet;
using err::LUMIERA_ERROR_LIFECYCLE;
namespace { // policy and configuration for test...
double ctxParameter = 1.0;
/**
* @note the test uses a rather elaborate result value setting
* - produces five distinct values
* - value range is symmetrical to origin
* - zero is defined as the _neutral value_
* - accepts a `size_t` hash value as basic input
*/
struct SymmetricFive
: function<Limited<int, 2,-2, 0>(size_t)>
{
/** by default use the hash directly as source of randomness */
static size_t defaultSrc (size_t hash) { return hash; }
/** Adaptor to handle further mapping functions */
template<class SIG>
struct Adaptor
{
static_assert (not sizeof(SIG), "Unable to adapt given functor.");
};
/** allow a mapping function rely on quantisation cycles */
template<typename RES>
struct Adaptor<RES(uint,uint)>
{
template<typename FUN>
static auto
build (FUN&& fun)
{
return [functor=std::forward<FUN>(fun)]
(size_t hash) -> _FunRet<FUN>
{
return functor(uint(hash/64), uint(hash%64));
};
}
};
/** inject external contextual state into a mapping function */
template<typename RES>
struct Adaptor<RES(size_t, double)>
{
template<typename FUN>
static auto
build (FUN&& fun)
{
return [functor=std::forward<FUN>(fun)]
(size_t hash) -> _FunRet<FUN>
{
return functor(hash, ctxParameter);
};
}
};
};
//
}//(End) Test config
using Draw = RandomDraw<SymmetricFive>;
/***********************************************************************************//**
* @test Verify a flexible builder for random-value generators; using a config template,
* these can be outfitted to use a suitable source of randomness and to produce
* values from a desired target type and limited range.
* - for this test, generated result values are ∈ [-2 .. 0 .. +2]
* - no actual randomness is used; rather a `size_t` challenge is
* sent in to verify precisely deterministic numeric results.
* @see random-draw.hpp
* @see vault::gear::TestChainLoad as usage example
* @see SchedulerStress_test
*/
class RandomDraw_test
: public Test
{
void
run (Arg)
{
simpleUse();
verify_policy();
verify_numerics();
verify_adaptMapping();
verify_dynamicChange();
}
/** @test demonstrate a basic usage scenario
*/
void
simpleUse()
{
auto draw = Draw().probability(0.5);
CHECK (draw( 0) == 0);
CHECK (draw( 16) == 0);
CHECK (draw( 32) == 1);
CHECK (draw( 40) == 2);
CHECK (draw( 48) == -2);
CHECK (draw( 56) == -1);
CHECK (draw( 64) == 0); // values repeat after 64 steps
CHECK (draw( 95) == 0); // ~ half of each cycle yields the »neutral value«
CHECK (draw( 96) == 1);
CHECK (draw(127) == -1);
CHECK (draw(128) == 0);
CHECK (draw(168) == 2);
CHECK (draw(256) == 0);
}
/** @test verify configuration through policy template
* - use the default policy, which takes no input values,
* but rather directly generates a random number; in this
* case here, input values are ∈ [0 .. 5]
* - define another policy template, to produce char values,
* while always requiring two input data values `(char,uint)`;
* moreover, define the `defaultSrc()` directly to produce the
* raw mapping values (double) using a custom formula; the
* resulting RandomDraw instance is now a function with
* two input arguments, producing char values.
*/
void
verify_policy()
{
auto d1 = RandomDraw<random_draw::LimitedRandomGenerate<5>>().probability(1.0);
uint v1 = d1();
CHECK (0 < v1 and v1 <=5);
struct SpecialPolicy
: function<Limited<char, 'Z','A'>(char,uint)>
{
static double defaultSrc (char b, uint off) { return fmod ((b-'A'+off)/double('Z'-'A'), 1.0); }
};
auto d2 = RandomDraw<SpecialPolicy>().probability(1.0);
CHECK (d2('A', 2) == 'D');
CHECK (d2('M',10) == 'X');
CHECK (d2('Y', 0) == 'Z');
CHECK (d2('Y',15) == 'P');
}
/** @test verify random number transformations.
* - use a Draw instance with result values `[-2..0..+2]`
* - values are evenly distributed within limits of quantisation
* - the probability parameter controls the amount of neutral results
* - maximum and minimum value settings will be respected
* - the interval [min..max] is independent from neutral value
* - probability defines the cases within [min..max] \ neutral
* - all other cases `q = 1 - p` will yield the neutral value
* - implausible max/min settings will be corrected automatically
*/
void
verify_numerics()
{
auto distribution = [](Draw const& draw)
{ // investigate value distribution
using Arr = std::array<int,5>;
Arr step{-1,-1,-1,-1,-1};
Arr freq{0};
for (uint i=0; i<128; ++i)
{
int res = draw(i);
CHECK (-2 <= res and res <= +2);
int idx = res+2;
freq[idx] += 1;
if (step[idx] < 0)
step[idx] = i;
}
_Fmt line{"val:%+d (%02d|%5.2f%%)\n"};
string report;
for (int idx=0; idx<5; ++idx)
{
report += line % (idx-2) % step[idx] % (100.0*freq[idx]/128);
}
return report;
};
auto draw = Draw();
string report{"+++| --empty-- \n"};
CHECK (draw( 0) == 0);
CHECK (draw( 32) == 0);
CHECK (draw( 96) == 0);
report += distribution(draw);
CHECK (report ==
"+++| --empty-- \n"
"val:-2 (-1| 0.00%)\n"
"val:-1 (-1| 0.00%)\n"
"val:+0 (00|100.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
draw.probability(1.0);
CHECK (draw( 0) == +1);
CHECK (draw( 15) == +1);
CHECK (draw( 16) == +2);
CHECK (draw( 31) == +2);
CHECK (draw( 32) == -2);
CHECK (draw( 47) == -2);
CHECK (draw( 48) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == +1);
CHECK (draw( 96) == -2);
report = "+++| p ≔ 1.0 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 \n"
"val:-2 (32|25.00%)\n"
"val:-1 (48|25.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (00|25.00%)\n"
"val:+2 (16|25.00%)\n"_expect);
draw.probability(0.99);
CHECK (draw( 0) == 0);
CHECK (draw( 1) == +1);
CHECK (draw( 16) == +1);
CHECK (draw( 17) == +2);
CHECK (draw( 32) == +2);
CHECK (draw( 33) == -2);
CHECK (draw( 48) == -2);
CHECK (draw( 49) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
CHECK (draw( 65) == +1);
CHECK (draw( 80) == +1); // 64+16
CHECK (draw( 82) == +2); // 64+17
CHECK (draw( 97) == -2); // 64+33
CHECK (draw(352) == +2); // 64+32+256
CHECK (draw(353) == -2); // 64+33+256
report = "+++| p ≔ 0.99 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.99 \n"
"val:-2 (33|25.00%)\n"
"val:-1 (49|23.44%)\n"
"val:+0 (00| 1.56%)\n"
"val:+1 (01|25.00%)\n"
"val:+2 (17|25.00%)\n"_expect);
draw.probability(0.98);
CHECK (draw( 0) == 0);
CHECK (draw( 1) == 0);
CHECK (draw( 2) == +1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
CHECK (draw( 65) == 0);
CHECK (draw( 66) == +1);
report = "+++| p ≔ 0.98 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.98 \n"
"val:-2 (33|25.00%)\n"
"val:-1 (49|23.44%)\n"
"val:+0 (00| 3.12%)\n"
"val:+1 (02|23.44%)\n"
"val:+2 (17|25.00%)\n"_expect);
draw.probability(0.97);
report = "+++| p ≔ 0.97 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.97 \n"
"val:-2 (33|25.00%)\n"
"val:-1 (49|23.44%)\n"
"val:+0 (00| 3.12%)\n"
"val:+1 (02|25.00%)\n"
"val:+2 (18|23.44%)\n"_expect);
draw.probability(0.75);
report = "+++| p ≔ 0.75 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.75 \n"
"val:-2 (40|18.75%)\n"
"val:-1 (52|18.75%)\n"
"val:+0 (00|25.00%)\n"
"val:+1 (16|18.75%)\n"
"val:+2 (28|18.75%)\n"_expect);
draw.probability(0.5);
report = "+++| p ≔ 0.50 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 \n"
"val:-2 (48|12.50%)\n"
"val:-1 (56|12.50%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (32|12.50%)\n"
"val:+2 (40|12.50%)\n"_expect);
draw.probability(0.2);
report = "+++| p ≔ 0.20 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.20 \n"
"val:-2 (58| 4.69%)\n"
"val:-1 (61| 4.69%)\n"
"val:+0 (00|81.25%)\n"
"val:+1 (52| 4.69%)\n"
"val:+2 (55| 4.69%)\n"_expect);
draw.probability(0.1);
report = "+++| p ≔ 0.10 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.10 \n"
"val:-2 (61| 3.12%)\n"
"val:-1 (63| 1.56%)\n"
"val:+0 (00|90.62%)\n"
"val:+1 (58| 3.12%)\n"
"val:+2 (60| 1.56%)\n"_expect);
// ══════════
draw.probability(1.0).shuffle(1);
CHECK (draw( 6) == +1); // 6*1
CHECK (draw( 6) == +1); // 6*2
CHECK (draw( 6) == +2); // 6*3
CHECK (draw( 6) == +2); // 6*4
CHECK (draw( 6) == +2); // 6*5
CHECK (draw( 6) == -2); // 6*6
CHECK (draw(16) == -1); // 16*7 %64 = 48
CHECK (draw(16) == +1); // 16*8 %64 = 0
report = "+++| p ≔ 1.0 +shuffle \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 +shuffle \n"
"val:-2 (03|25.00%)\n"
"val:-1 (04|25.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (00|25.00%)\n"
"val:+2 (02|25.00%)\n"_expect);
draw.shuffle(0);
CHECK (draw(16) == +2); // shuffling disabled
CHECK (draw(16) == +2); // values reproducible
CHECK (draw(32) == -2);
CHECK (draw(32) == -2);
CHECK (draw(16) == +2);
CHECK (draw(16) == +2);
// ═════════
draw.probability(0.5).maxVal(1);
CHECK (draw( 0) == 0);
CHECK (draw( 16) == 0);
CHECK (draw( 31) == 0);
CHECK (draw( 32) == +1);
CHECK (draw( 42) == +1);
CHECK (draw( 43) == -2);
CHECK (draw( 53) == -2);
CHECK (draw( 54) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
CHECK (draw( 95) == 0);
CHECK (draw( 96) == +1);
report = "+++| p ≔ 0.50 max ≔ 1 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 max ≔ 1 \n"
"val:-2 (43|17.19%)\n"
"val:-1 (54|15.62%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (32|17.19%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
draw.probability(1.0).maxVal(1);
CHECK (draw( 0) == +1);
CHECK (draw( 16) == +1);
CHECK (draw( 21) == +1);
CHECK (draw( 22) == -2);
CHECK (draw( 42) == -2);
CHECK (draw( 43) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == +1);
CHECK (draw( 85) == +1);
CHECK (draw( 86) == -2);
CHECK (draw( 96) == -2);
report = "+++| p ≔ 1.0 max ≔ 1 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 max ≔ 1 \n"
"val:-2 (22|32.81%)\n"
"val:-1 (43|32.81%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (00|34.38%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
// ═════════
draw.probability(0.5).maxVal(0);
CHECK (draw( 0) == 0);
CHECK (draw( 31) == 0);
CHECK (draw( 32) == -2);
CHECK (draw( 47) == -2);
CHECK (draw( 48) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
CHECK (draw( 95) == 0);
CHECK (draw( 96) == -2);
report = "+++| p ≔ 0.50 max ≔ 0 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 max ≔ 0 \n"
"val:-2 (32|25.00%)\n"
"val:-1 (48|25.00%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
draw.probability(1.0).maxVal(0);
CHECK (draw( 0) == -2);
CHECK (draw( 31) == -2);
CHECK (draw( 32) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == -2);
CHECK (draw( 96) == -1);
report = "+++| p ≔ 1.0 max ≔ 0 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 max ≔ 0 \n"
"val:-2 (00|50.00%)\n"
"val:-1 (32|50.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
// ═════════
draw.probability(0.5).maxVal(-1);
CHECK (draw( 32) == -2);
CHECK (draw( 47) == -2);
CHECK (draw( 48) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
CHECK (draw( 95) == 0);
CHECK (draw( 96) == -2);
report = "+++| p ≔ 0.50 max ≔ -1 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 max ≔ -1 \n"
"val:-2 (32|25.00%)\n"
"val:-1 (48|25.00%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
draw.probability(1.0).maxVal(-1);
CHECK (draw( 0) == -2);
CHECK (draw( 31) == -2);
CHECK (draw( 32) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == -2);
report = "+++| p ≔ 1.0 max ≔ -1 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 max ≔ -1 \n"
"val:-2 (00|50.00%)\n"
"val:-1 (32|50.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
// ═════════
draw.probability(0.5).maxVal(2).minVal(1);
CHECK (draw( 32) == +1);
CHECK (draw( 48) == +2);
CHECK (draw( 63) == +2);
CHECK (draw( 64) == 0);
report = "+++| p ≔ 0.50 min ≔ 1 max ≔ 2 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 min ≔ 1 max ≔ 2 \n"
"val:-2 (-1| 0.00%)\n"
"val:-1 (-1| 0.00%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (32|25.00%)\n"
"val:+2 (48|25.00%)\n"_expect);
draw.probability(1.0).maxVal(2).minVal(1);
CHECK (draw( 0) == +1);
CHECK (draw( 32) == +2);
CHECK (draw( 63) == +2);
CHECK (draw( 64) == +1);
report = "+++| p ≔ 1.0 min ≔ 1 max ≔ 2 \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 1.0 min ≔ 1 max ≔ 2 \n"
"val:-2 (-1| 0.00%)\n"
"val:-1 (-1| 0.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (00|50.00%)\n"
"val:+2 (32|50.00%)\n"_expect);
// ═════════
draw.probability(0.5).maxVal(0);
CHECK (draw( 32) == -1);
CHECK (draw( 63) == -1);
CHECK (draw( 64) == 0);
report = "+++| p ≔ 0.50 max ≔ 0 (-> min ≔ -1) \n";
report += distribution(draw);
CHECK (report ==
"+++| p ≔ 0.50 max ≔ 0 (-> min ≔ -1) \n"
"val:-2 (-1| 0.00%)\n"
"val:-1 (32|50.00%)\n"
"val:+0 (00|50.00%)\n"
"val:+1 (-1| 0.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
// ═════════
draw.fixedVal(1);
report = "+++| fixedVal(1) \n";
report += distribution(draw);
CHECK (report ==
"+++| fixedVal(1) \n"
"val:-2 (-1| 0.00%)\n"
"val:-1 (-1| 0.00%)\n"
"val:+0 (-1| 0.00%)\n"
"val:+1 (00|100.00%)\n"
"val:+2 (-1| 0.00%)\n"_expect);
}
/** @test bind custom mapping transformation functions.
* - use different translation into positional values
* as input for the actual result value mapping;
* - use a mapping function with different arguments,
* which is wired by the appropriate Adapter from the Policy;
* - moreover, the concrete Policy may tap into the context, which is
* demonstrated here by accessing a global variable. In practice,
* this capability allows to accept custom types as data source.
*/
void
verify_adaptMapping()
{
// Note: no special Adapter required for the following function,
// since it takes the same arguments as our RandomDraw (size_t);
// moreover, since the function yields a double, the adapter scheme
// concludes that this function wants to feed directly into the
// primary mapping function RandomDraw::limited(double)
auto d1 = Draw([](size_t hash) -> double { return hash / 10.0; });
CHECK (d1( 0) == +1);
CHECK (d1( 1) == +1);
CHECK (d1( 2) == +1);
CHECK (d1( 3) == +2);
CHECK (d1( 4) == +2);
CHECK (d1( 5) == -2);
CHECK (d1( 6) == -2);
CHECK (d1( 7) == -2);
CHECK (d1( 8) == -1);
CHECK (d1( 9) == -1);
CHECK (d1(10) == 0);
CHECK (d1(11) == 0);
CHECK (d1(12) == 0);
CHECK (d1(13) == 0);
d1.probability(0.4);
CHECK (d1( 0) == 0);
CHECK (d1( 1) == 0);
CHECK (d1( 2) == 0);
CHECK (d1( 3) == 0);
CHECK (d1( 4) == 0);
CHECK (d1( 5) == 0);
CHECK (d1( 6) == +1); // probability 0.4
CHECK (d1( 7) == +2);
CHECK (d1( 8) == -2);
CHECK (d1( 9) == -1);
CHECK (d1(10) == 0);
d1.minVal(-1).probability(0.7);
CHECK (d1( 0) == 0);
CHECK (d1( 1) == 0);
CHECK (d1( 2) == 0);
CHECK (d1( 3) == 0);
CHECK (d1( 4) == +1); // probability 0.7
CHECK (d1( 5) == +1);
CHECK (d1( 6) == +2);
CHECK (d1( 7) == +2);
CHECK (d1( 8) == -1);
CHECK (d1( 9) == -1);
CHECK (d1(10) == 0);
// The next example demonstrates accepting special input arguments;
// as defined in the policy, this function will get the `(div, mod)`
// of the hash with modulus 64
auto d2 = Draw([](uint cycle, uint rem){ return double(rem) / ((cycle+1)*5); });
CHECK (d2( 0) == +1);
CHECK (d2( 1) == +1);
CHECK (d2( 2) == +2);
CHECK (d2( 3) == -2);
CHECK (d2( 4) == -1); // the first cycle is only 5 steps long (0+1)*5
CHECK (d2( 5) == 0);
CHECK (d2( 6) == 0);
CHECK (d2( 7) == 0);
CHECK (d2( 8) == 0);
CHECK (d2( 9) == 0);
CHECK (d2(10) == 0);
CHECK (d2(63) == 0);
CHECK (d2(64) == +1); // the second cycle starts here...
CHECK (d2(65) == +1);
CHECK (d2(66) == +1);
CHECK (d2(67) == +2);
CHECK (d2(68) == +2);
CHECK (d2(69) == -2);
CHECK (d2(70) == -2);
CHECK (d2(71) == -2);
CHECK (d2(72) == -1);
CHECK (d2(73) == -1);
CHECK (d2(74) == 0); // and is 10 steps long (same pattern as in the first example above)
CHECK (d2(75) == 0);
// The next example uses the other Adapter variant, which „sneaks in“ a context value
// Moreover, we can change the mapping function of an existing RandomDraw, as demonstrated here
d2.mapping([](size_t hash, double ctx){ return hash / ctx; });
ctxParameter = 4.0;
CHECK (d2( 0) == +1);
CHECK (d2( 1) == +2);
CHECK (d2( 2) == -2);
CHECK (d2( 3) == -1); // cycle-length: 4
CHECK (d2( 4) == 0);
CHECK (d2( 5) == 0);
CHECK (d2( 6) == 0);
CHECK (d2( 7) == 0);
CHECK (d2( 8) == 0);
CHECK (d2( 9) == 0);
CHECK (d2(10) == 0);
ctxParameter = 8.0;
CHECK (d2( 0) == +1);
CHECK (d2( 1) == +1);
CHECK (d2( 2) == +2);
CHECK (d2( 3) == +2);
CHECK (d2( 4) == -2);
CHECK (d2( 5) == -2);
CHECK (d2( 6) == -1);
CHECK (d2( 7) == -1); // cycle-length: 8
CHECK (d2( 8) == 0);
CHECK (d2( 9) == 0);
CHECK (d2(10) == 0);
// and can of course dynamically tweak the mapping profile...
d2.maxVal(0).probability(0.5);
CHECK (d2( 0) == 0);
CHECK (d2( 1) == 0);
CHECK (d2( 2) == 0);
CHECK (d2( 3) == 0);
CHECK (d2( 4) == -2); // start here due to probability 0.5
CHECK (d2( 5) == -2);
CHECK (d2( 6) == -1);
CHECK (d2( 7) == -1); // cycle-length: 8
CHECK (d2( 8) == 0);
CHECK (d2( 9) == 0);
CHECK (d2(10) == 0);
// NOTE: once a custom mapping function has been installed,
// the object can no longer be moved, due to reference binding.
VERIFY_ERROR (LIFECYCLE, Draw dx{move(d2)} );
}
/** @test change the generation profile dynamically, based on current input;
* in the example here, the probability is manipulated in each cycle.
*/
void
verify_dynamicChange()
{
auto d1 = Draw([](uint cycle, uint)
{ // dynamically control probability
return Draw().probability((cycle+1)*0.25);
});
CHECK (d1( 0) == 0);
CHECK (d1( 8) == 0);
CHECK (d1( 16) == 0);
CHECK (d1( 24) == 0);
CHECK (d1( 32) == 0);
CHECK (d1( 40) == 0);
CHECK (d1( 48) == 1); // 1st cycle: 25% probability
CHECK (d1( 56) == -2);
CHECK (d1( 63) == -1);
CHECK (d1( 64 +0) == 0);
CHECK (d1( 64 +8) == 0);
CHECK (d1( 64+16) == 0);
CHECK (d1( 64+24) == 0);
CHECK (d1( 64+32) == 1); // 2nd cycle: 50% probability
CHECK (d1( 64+40) == 2);
CHECK (d1( 64+48) == -2);
CHECK (d1( 64+56) == -1);
CHECK (d1( 64+63) == -1);
CHECK (d1(128 +0) == 0);
CHECK (d1(128 +8) == 0);
CHECK (d1(128 +16) == 1); // 3rd cycle: 75% probability
CHECK (d1(128 +24) == 1);
CHECK (d1(128 +32) == 2);
CHECK (d1(128 +40) == -2);
CHECK (d1(128 +48) == -2);
CHECK (d1(128 +56) == -1);
CHECK (d1(128 +63) == -1);
CHECK (d1(128+64 +0) == 1); // 4rth cycle: 100% probability
CHECK (d1(128+64 +8) == 1);
CHECK (d1(128+64+16) == 2);
CHECK (d1(128+64+24) == 2);
CHECK (d1(128+64+32) == -2);
CHECK (d1(128+64+40) == -2);
CHECK (d1(128+64+48) == -1);
CHECK (d1(128+64+56) == -1);
CHECK (d1(128+64+63) == -1);
CHECK (d1(128+64+64) == 1);
}
};
/** Register this test class... */
LAUNCHER (RandomDraw_test, "unit common");
}} // namespace lib::test
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