move code

1 files changed, 99 insertions, 0 deletions

diff --git a/eval/src/tests/eval/gbdt/model.cpp b/eval/src/tests/eval/gbdt/model.cpp
new file mode 100644
index 00000000000..e125d9e77d2
--- /dev/null
+++ b/eval/src/tests/eval/gbdt/model.cpp
@@ -0,0 +1,99 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <random>
+#include <vespa/vespalib/eval/function.h>
+
+using vespalib::make_string;
+using vespalib::eval::Function;
+
+//-----------------------------------------------------------------------------
+
+class Model
+{
+private:
+    std::mt19937 _gen;
+    size_t _less_percent;
+
+    size_t get_int(size_t min, size_t max) {
+        std::uniform_int_distribution<size_t> dist(min, max);
+        return dist(_gen);
+    }
+
+    double get_real(double min, double max) {
+        std::uniform_real_distribution<double> dist(min, max);
+        return dist(_gen);
+    }
+
+    std::string make_feature_name() {
+        size_t max_feature = 2;
+        while ((max_feature < 1024) && (get_int(0, 99) < 50)) {
+            max_feature *= 2;
+        }
+        return make_string("feature_%zu", get_int(1, max_feature));
+    }
+
+    std::string make_cond() {
+        if (get_int(1,100) > _less_percent) {
+            return make_string("(%s in [%g,%g,%g])",
+                               make_feature_name().c_str(),
+                               get_int(0, 4) / 4.0,
+                               get_int(0, 4) / 4.0,
+                               get_int(0, 4) / 4.0);
+        } else {
+            return make_string("(%s<%g)",
+                               make_feature_name().c_str(),
+                               get_real(0.0, 1.0));
+        }
+    }
+
+public:
+    explicit Model(size_t seed = 5489u) : _gen(seed), _less_percent(80) {}
+
+    Model &less_percent(size_t value) {
+        _less_percent = value;
+        return *this;
+    }
+
+    std::string make_tree(size_t size) {
+        assert(size > 0);
+        if (size == 1) {
+            return make_string("%g", get_real(0.0, 1.0));
+        }
+        size_t pivot = get_int(1, size - 1);
+        return make_string("if(%s,%s,%s)",
+                           make_cond().c_str(),
+                           make_tree(pivot).c_str(),
+                           make_tree(size - pivot).c_str());
+    }
+
+    std::string make_forest(size_t num_trees, size_t tree_sizes) {
+        assert(num_trees > 0);
+        vespalib::string forest = make_tree(tree_sizes);
+        for (size_t i = 1; i < num_trees; ++i) {
+            forest.append("+");
+            forest.append(make_tree(tree_sizes));
+        }
+        return forest;
+    }
+};
+
+//-----------------------------------------------------------------------------
+
+struct ForestParams {
+    size_t model_seed;
+    size_t less_percent;
+    size_t tree_size;
+    ForestParams(size_t model_seed_in, size_t less_percent_in, size_t tree_size_in)
+        : model_seed(model_seed_in), less_percent(less_percent_in), tree_size(tree_size_in) {}
+};
+
+//-----------------------------------------------------------------------------
+
+Function make_forest(const ForestParams &params, size_t num_trees) {
+    return Function::parse(Model(params.model_seed)
+                           .less_percent(params.less_percent)
+                           .make_forest(num_trees, params.tree_size));
+}
+
+//-----------------------------------------------------------------------------