skia2/tools/Stats.h
Mike Klein c0bd9f9fe5 rewrite includes to not need so much -Ifoo
Current strategy: everything from the top

Things to look at first are the manual changes:

   - added tools/rewrite_includes.py
   - removed -Idirectives from BUILD.gn
   - various compile.sh simplifications
   - tweak tools/embed_resources.py
   - update gn/find_headers.py to write paths from the top
   - update gn/gn_to_bp.py SkUserConfig.h layout
     so that #include "include/config/SkUserConfig.h" always
     gets the header we want.

No-Presubmit: true
Change-Id: I73a4b181654e0e38d229bc456c0d0854bae3363e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/209706
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
2019-04-24 16:27:11 +00:00

80 lines
2.3 KiB
C

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef Stats_DEFINED
#define Stats_DEFINED
#include "include/core/SkString.h"
#include "include/private/SkFloatingPoint.h"
#include "src/core/SkTSort.h"
#ifdef SK_BUILD_FOR_WIN
static const char* kBars[] = { ".", "o", "O" };
#else
static const char* kBars[] = { "", "", "", "", "", "", "", "" };
#endif
struct Stats {
Stats(const SkTArray<double>& samples, bool want_plot) {
int n = samples.count();
if (!n) {
min = max = mean = var = median = 0;
return;
}
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 = sk_ieee_double_divide(err, n-1);
SkAutoTMalloc<double> sorted(n);
memcpy(sorted.get(), samples.begin(), n * sizeof(double));
SkTQSort(sorted.get(), sorted.get() + n - 1);
median = sorted[n/2];
// Normalize samples to [min, max] in as many quanta as we have distinct bars to print.
for (int i = 0; want_plot && i < n; i++) {
if (min == max) {
// All samples are the same value. Don't divide by zero.
plot.append(kBars[0]);
continue;
}
double s = samples[i];
s -= min;
s /= (max - min);
s *= (SK_ARRAY_COUNT(kBars) - 1);
const size_t bar = (size_t)(s + 0.5);
SkASSERT_RELEASE(bar < SK_ARRAY_COUNT(kBars));
plot.append(kBars[bar]);
}
}
double min;
double max;
double mean; // Estimate of population mean.
double var; // Estimate of population variance.
double median;
SkString plot; // A single-line bar chart (_not_ histogram) of the samples.
};
#endif//Stats_DEFINED