skia2/tools/Stats.h
mtklein 90c471e73f Refine bench_record and bench_playback:
- use high-precision wall timer only
  - warm caches once before measuring
  - measure independent samples, calculating statistics
  - add --verbose to control how much data we output

Also removed some unloved features from bench_record.

BUG=skia:
R=jcgregorio@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/338203002
2014-06-16 14:04:34 -07:00

33 lines
780 B
C

#ifndef Stats_DEFINED
#define Stats_DEFINED
struct Stats {
Stats(const double samples[], int n) {
min = samples[0];
max = samples[0];
for (int i = 0; i < n; i++) {
if (samples[i] < min) { min = samples[i]; }
if (samples[i] > max) { max = samples[i]; }
}
double sum = 0.0;
for (int i = 0 ; i < n; i++) {
sum += samples[i];
}
mean = sum / n;
double err = 0.0;
for (int i = 0 ; i < n; i++) {
err += (samples[i] - mean) * (samples[i] - mean);
}
var = err / (n-1);
}
double min;
double max;
double mean; // Estimate of population mean.
double var; // Estimate of population variance.
};
#endif//Stats_DEFINED