From ce033a24a363170d7b130a5defdc8cd8241cc98d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Holzm=C3=BCller?= <david.holzmueller@online.de>
Date: Sat, 13 Apr 2019 11:13:40 +0200
Subject: [PATCH] improved performance plotting: more runs, better stopping
 criterion, warm-up

---
 test/main.cpp        |  5 +++--
 test/performance.cpp | 30 +++++++++++++++++++++++++++---
 2 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/test/main.cpp b/test/main.cpp
index 13c3c8e..46e8a9d 100644
--- a/test/main.cpp
+++ b/test/main.cpp
@@ -37,6 +37,7 @@ void runFunctions() {
   // std::cout << rhs << "\n";
 
   Timer timer;
+  timer.reset();
   op.prepareSolve();
   // auto result = fsi::interpolate(f, it, phi, x);
   std::cout << "Time for prepareSolve(): " << timer.elapsed() << " s\n";
@@ -67,6 +68,6 @@ void runFunctions() {
 
 // using namespace fsi;
 int main() {
-  runFunctions();
-  // measurePerformance();
+  // runFunctions();
+  measurePerformance();
 }
diff --git a/test/performance.cpp b/test/performance.cpp
index 9ac77fc..d00b986 100644
--- a/test/performance.cpp
+++ b/test/performance.cpp
@@ -48,17 +48,40 @@ void measurePerformance() {
   // if exceeded, we do not try higher numbers of points
   double maxRuntime = 2.0;
 
-  // perform 2*k+1 measurements per configuration
-  size_t k = 1;
+  // small value for denominator of a fraction
+  double epsilon = 0.01;
+
+  // perform 2*k+1 measurements per configuration, then take median
+  size_t k = 2;
+
+  // warm-up
+
+  std::cout << "Warm-up\n";
+
+  size_t d_warmup = 5;
+  size_t bound_warmup = 60;
+
+  fsi::BoundedSumIterator it(d_warmup, bound_warmup);
+  std::vector<MonomialFunctions> phi(d_warmup);
+  std::vector<GoldenPointDistribution> x(d_warmup);
+
+  auto rhs = evaluateFunction(it, f, x);
+  auto op = createInterpolationOperator(it, phi, x);
+
+  op.solve(rhs);
+
+  std::cout << "Warm-up finished\n";
 
   for (size_t d : dimensions) {
     std::cout << "Dimension: " << d << "\n";
 
     size_t last_num_points = 0;
+    double last_runtime = 0.0;
 
     for (size_t bound = 1; true; ++bound) {
       size_t num_points = fsi::binom(bound + d, d);
       if (num_points > maxNumPoints) break;
+      if (num_points / (last_num_points + epsilon) * last_runtime > maxRuntime) break;
       if (num_points < last_num_points * minQuotient) continue;
 
       last_num_points = num_points;
@@ -74,6 +97,7 @@ void measurePerformance() {
             auto op = createInterpolationOperator(it, phi, x);
 
             Timer timer;
+            timer.reset();
             op.solve(rhs);
             double time = timer.elapsed();
             std::cout << "Time for solve(): " << time << " s\n";
@@ -83,7 +107,7 @@ void measurePerformance() {
 
       stream << d << ", " << bound << ", " << fsi::binom(bound + d, d) << ", " << runtime << "\n";
 
-      if (runtime > maxRuntime) break;
+      last_runtime = runtime;
     }
   }