From 405e6b6b693234024ae541a74cfb9733f3b8f09d Mon Sep 17 00:00:00 2001 From: Berthold Stoeger Date: Wed, 6 Jan 2021 14:17:51 +0100 Subject: [PATCH] statistics: fix chart features: regression line and median/mean The coordinates of these were calculated when creating the feature. This is wrong, because the min/max values of the axes can change on resize to get "nice" number. Therefore, recalculate after resizing. This means that the general "LineMarker" class has to be split into two classes, one for regression lines and one for median/mean markers. Signed-off-by: Berthold Stoeger --- stats/statsaxis.cpp | 6 ++++ stats/statsaxis.h | 1 + stats/statsview.cpp | 74 ++++++++++++++++++++++++++++----------------- stats/statsview.h | 23 ++++++++++---- 4 files changed, 70 insertions(+), 34 deletions(-) diff --git a/stats/statsaxis.cpp b/stats/statsaxis.cpp index 3bdb8e427..ebd41fb94 100644 --- a/stats/statsaxis.cpp +++ b/stats/statsaxis.cpp @@ -52,6 +52,12 @@ std::pair StatsAxis::minMax() const return { min, max }; } +std::pair StatsAxis::minMaxScreen() const +{ + return horizontal ? std::make_pair(zeroOnScreen, zeroOnScreen + size) + : std::make_pair(zeroOnScreen, zeroOnScreen - size); +} + void StatsAxis::setRange(double minIn, double maxIn) { min = minIn; diff --git a/stats/statsaxis.h b/stats/statsaxis.h index 150deb087..d9fdd6b41 100644 --- a/stats/statsaxis.h +++ b/stats/statsaxis.h @@ -20,6 +20,7 @@ public: virtual ~StatsAxis(); // Returns minimum and maximum of shown range, not of data points. std::pair minMax() const; + std::pair minMaxScreen() const; // minimum and maximum in screen coordinates double width() const; // Only supported by vertical axes. Only valid after setSize(). double height() const; // Only supported for horizontal axes. Always valid. diff --git a/stats/statsview.cpp b/stats/statsview.cpp index d6da093b3..f42296fc2 100644 --- a/stats/statsview.cpp +++ b/stats/statsview.cpp @@ -125,7 +125,9 @@ void StatsView::plotAreaChanged(const QRectF &r) series->updatePositions(); for (QuartileMarker &marker: quartileMarkers) marker.updatePosition(); - for (LineMarker &marker: lineMarkers) + for (RegressionLine &line: regressionLines) + line.updatePosition(); + for (HistogramMarker &marker: histogramMarkers) marker.updatePosition(); if (legend) legend->resize(); @@ -211,7 +213,8 @@ void StatsView::reset() legend.reset(); series.clear(); quartileMarkers.clear(); - lineMarkers.clear(); + regressionLines.clear(); + histogramMarkers.clear(); chart->removeAllSeries(); grid.reset(); axes.clear(); @@ -716,37 +719,25 @@ void StatsView::QuartileMarker::updatePosition() x + quartileMarkerSize / 2.0, y); } -StatsView::LineMarker::LineMarker(QPointF from, QPointF to, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis) : +StatsView::RegressionLine::RegressionLine(double a, double b, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis) : item(new QGraphicsLineItem(chart)), xAxis(xAxis), yAxis(yAxis), - from(from), to(to) + a(a), b(b) { item->setZValue(ZValues::chartFeatures); item->setPen(pen); - updatePosition(); } -void StatsView::LineMarker::updatePosition() +void StatsView::RegressionLine::updatePosition() { if (!xAxis || !yAxis) return; - double x1 = xAxis->toScreen(from.x()); - double y1 = yAxis->toScreen(from.y()); - double x2 = xAxis->toScreen(to.x()); - double y2 = yAxis->toScreen(to.y()); - item->setLine(x1, y1, x2, y2); -} - -void StatsView::addLinearRegression(double a, double b, double minX, double maxX, double minY, double maxY, StatsAxis *xAxis, StatsAxis *yAxis) -{ - // Sanity check: line above or below chart + auto [minX, maxX] = xAxis->minMax(); + auto [minY, maxY] = yAxis->minMax(); double y1 = a * minX + b; double y2 = a * maxX + b; - if ((y1 <= minY && y2 <= minY) || (y1 >= maxY && y2 >= maxY)) - return; - // If not fully inside drawing region, do clipping. With the check above this guarantees that a != 0, - // but owing to floating point imprecision, let's test again. + // If not fully inside drawing region, do clipping. if ((y1 < minY || y1 > maxY || y2 < minY || y2 > maxY) && fabs(a) > 0.0001) { // Intersections with y = minY and y = maxY lines double intersect_x1 = (minY - b) / a; @@ -756,14 +747,42 @@ void StatsView::addLinearRegression(double a, double b, double minX, double maxX minX = std::max(minX, intersect_x1); maxX = std::min(maxX, intersect_x2); } - lineMarkers.emplace_back(QPointF(minX, a * minX + b), QPointF(maxX, a * maxX + b), QPen(Qt::red), chart, xAxis, yAxis); + item->setLine(xAxis->toScreen(minX), yAxis->toScreen(a * minX + b), + xAxis->toScreen(maxX), yAxis->toScreen(a * maxX + b)); } -void StatsView::addHistogramMarker(double pos, double low, double high, const QPen &pen, bool isHorizontal, StatsAxis *xAxis, StatsAxis *yAxis) +StatsView::HistogramMarker::HistogramMarker(double val, bool horizontal, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis) : + item(new QGraphicsLineItem(chart)), + xAxis(xAxis), yAxis(yAxis), + val(val), horizontal(horizontal) { - QPointF from = isHorizontal ? QPointF(low, pos) : QPointF(pos, low); - QPointF to = isHorizontal ? QPointF(high, pos) : QPointF(pos, high); - lineMarkers.emplace_back(from, to, pen, chart, xAxis, yAxis); + item->setZValue(ZValues::chartFeatures); + item->setPen(pen); +} + +void StatsView::HistogramMarker::updatePosition() +{ + if (!xAxis || !yAxis) + return; + if (horizontal) { + double y = yAxis->toScreen(val); + auto [x1, x2] = xAxis->minMaxScreen(); + item->setLine(x1, y, x2, y); + } else { + double x = xAxis->toScreen(val); + auto [y1, y2] = yAxis->minMaxScreen(); + item->setLine(x, y1, x, y2); + } +} + +void StatsView::addHistogramMarker(double pos, const QPen &pen, bool isHorizontal, StatsAxis *xAxis, StatsAxis *yAxis) +{ + histogramMarkers.emplace_back(pos, isHorizontal, pen, chart, xAxis, yAxis); +} + +void StatsView::addLinearRegression(double a, double b, double minX, double maxX, double minY, double maxY, StatsAxis *xAxis, StatsAxis *yAxis) +{ + regressionLines.emplace_back(a, b, QPen(Qt::red), chart, xAxis, yAxis); } // Yikes, we get our data in different kinds of (bin, value) pairs. @@ -812,7 +831,6 @@ void StatsView::plotHistogramCountChart(const std::vector &dives, int total = getTotalCount(categoryBins); StatsAxis *valAxis = createCountAxis(maxCategoryCount, isHorizontal); - double chartHeight = valAxis->minMax().second; if (isHorizontal) setAxes(valAxis, catAxis); @@ -840,14 +858,14 @@ void StatsView::plotHistogramCountChart(const std::vector &dives, QPen meanPen(Qt::green); meanPen.setWidth(2); if (!std::isnan(mean)) - addHistogramMarker(mean, 0.0, chartHeight, meanPen, isHorizontal, xAxis, yAxis); + addHistogramMarker(mean, meanPen, isHorizontal, xAxis, yAxis); } if (showMedian) { double median = categoryVariable->quartiles(dives).q2; QPen medianPen(Qt::red); medianPen.setWidth(2); if (!std::isnan(median)) - addHistogramMarker(median, 0.0, chartHeight, medianPen, isHorizontal, xAxis, yAxis); + addHistogramMarker(median, medianPen, isHorizontal, xAxis, yAxis); } } } diff --git a/stats/statsview.h b/stats/statsview.h index 92dbedf03..fd8ec1e2c 100644 --- a/stats/statsview.h +++ b/stats/statsview.h @@ -106,17 +106,27 @@ private: void updatePosition(); }; - // A general line marker - struct LineMarker { + // A regression line + struct RegressionLine { std::unique_ptr item; StatsAxis *xAxis, *yAxis; - QPointF from, to; // In local coordinates + double a, b; // y = ax + b void updatePosition(); - LineMarker(QPointF from, QPointF to, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis); + RegressionLine(double a, double b, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis); + }; + + // A line marking median or mean in histograms + struct HistogramMarker { + std::unique_ptr item; + StatsAxis *xAxis, *yAxis; + double val; + bool horizontal; + void updatePosition(); + HistogramMarker(double val, bool horizontal, QPen pen, QtCharts::QChart *chart, StatsAxis *xAxis, StatsAxis *yAxis); }; void addLinearRegression(double a, double b, double minX, double maxX, double minY, double maxY, StatsAxis *xAxis, StatsAxis *yAxis); - void addHistogramMarker(double pos, double low, double high, const QPen &pen, bool isHorizontal, StatsAxis *xAxis, StatsAxis *yAxis); + void addHistogramMarker(double pos, const QPen &pen, bool isHorizontal, StatsAxis *xAxis, StatsAxis *yAxis); StatsState state; QtCharts::QChart *chart; @@ -126,7 +136,8 @@ private: std::vector> series; std::unique_ptr legend; std::vector quartileMarkers; - std::vector lineMarkers; + std::vector regressionLines; + std::vector histogramMarkers; std::unique_ptr title; StatsSeries *highlightedSeries; StatsAxis *xAxis, *yAxis;