Mercurial > hg > svcore
view base/LogRange.cpp @ 1455:ec9e65fcf749
The use of the begin/end pairs here just seems to cause too many rows to be deleted (from the visual representation, not the underlying model). Things apparently work better if we just modify the underlying model and let the change signals percolate back up again. To that end, update the change handlers so as to cover their proper ranges with dataChanged signals.
author | Chris Cannam |
---|---|
date | Mon, 23 Apr 2018 16:03:35 +0100 |
parents | 7e3532d56abb |
children |
line wrap: on
line source
/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2006 Chris Cannam. 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. See the file COPYING included with this distribution for more information. */ #include "LogRange.h" #include "system/System.h" #include <algorithm> #include <iostream> #include <cmath> void LogRange::mapRange(double &min, double &max, double logthresh) { static double eps = 1e-10; // ensure that max > min: if (min > max) std::swap(min, max); if (max == min) max = min + 1; if (min >= 0.0) { // and max > min, so we know min >= 0 and max > 0 max = log10(max); if (min == 0.0) min = std::min(logthresh, max); else min = log10(min); } else if (max <= 0.0) { // and max > min, so we know min < 0 and max <= 0 min = log10(-min); if (max == 0.0) max = std::min(logthresh, min); else max = log10(-max); std::swap(min, max); } else { // min < 0 and max > 0 max = log10(std::max(max, -min)); min = std::min(logthresh, max); } if (fabs(max - min) < eps) min = max - 1; } double LogRange::map(double value, double thresh) { if (value == 0.0) return thresh; return log10(fabs(value)); } double LogRange::unmap(double value) { return pow(10.0, value); } static double sd(const std::vector<double> &values, int start, int n) { double sum = 0.0, mean = 0.0, variance = 0.0; for (int i = 0; i < n; ++i) { sum += values[start + i]; } mean = sum / n; for (int i = 0; i < n; ++i) { double diff = values[start + i] - mean; variance += diff * diff; } variance = variance / n; return sqrt(variance); } bool LogRange::shouldUseLogScale(std::vector<double> values) { // Principle: Partition the data into two sets around the median; // calculate the standard deviation of each set; if the two SDs // are very different, it's likely that a log scale would be good. int n = int(values.size()); if (n < 4) return false; std::sort(values.begin(), values.end()); int mi = n / 2; double sd0 = sd(values, 0, mi); double sd1 = sd(values, mi, n - mi); SVDEBUG << "LogRange::useLogScale: sd0 = " << sd0 << ", sd1 = " << sd1 << endl; if (sd0 == 0 || sd1 == 0) return false; // I wonder what method of determining "one sd much bigger than // the other" would be appropriate here... if (std::max(sd0, sd1) / std::min(sd0, sd1) > 10.) return true; else return false; }