Hi @noonchen

We're not opposed to adding box-plot support, but given that those kinds of plots don't typically undergo rapid updating, we're probably not going to get much interest from maintainers on implementing it (I do not speak for other maintainers besides myself so I could be mistaken here).

We do have an example that shows how to do your own boxplot which may be of help if you want to roll out your own thing; the code isn't too bad.

Example: https://github.com/pyqtgraph/pyqtgraph/blob/master/pyqtgraph/examples/customGraphicsItem.py

Result:

If you all do roll out your own thing, and want to contribute it to the library, we would certainly be receptive to that!

Hi @j9ac9k,

Thanks for the example! , I looked into the code and I think I can implement one on my own. If it looks good I'll create a pr.

Hi @j9ac9k ,

I am working on the boxplot feature, it is almost finished, but I have encountered some difficulties in drawing outlier points, hope you can give me some advice.

The outlier points are scatter points drew at both ends of boxplot, it would be expensive to embed a ScatterPlotItem so that I tried to copy some logics from scatter plot, but these scatter points are distorted, the expected output should look like scatter plot with pxMode=False.

Code can be found here.

I was able to draw your outlier points in device coordinates by moving the relevant code out of QPicture and into the paint() method itself. It seems that there are some limitations as to what can be drawn into a QPicture.

There are some other things to handle, which would be computing the boundingRect to include the outliers.

    def paint(self, p, *args):
        if self.picture is None:
            self.generatePicture()
        p.drawPicture(0, 0, self.picture)

        if not self.opts["outlier"]:
            return

        # outlier related style
        if isinstance(self.opts["symbol"], QtGui.QPainterPath):
            symbol = self.opts["symbol"]
        else:
            symbol = QtGui.QPainterPath()
            symbol.addEllipse(QRectF(-0.5, -0.5, 1, 1))
        symbolPen = pg.mkPen(self.opts["symbolPen"])
        symbolSize = 5 if self.opts["symbolSize"] is None else self.opts["symbolSize"]
        symbolBrush = pg.mkBrush(self.opts["symbolBrush"])

        p.setPen(symbolPen)
        p.setBrush(symbolBrush)
        for pos, outliers in self.outlierData.items():
            for o in outliers:
                x, y = (pos, o)
                pt = self.mapToScene(x, y)
                tr = QtGui.QTransform.fromTranslate(pt.x(), pt.y()).scale(symbolSize, symbolSize)
                p.setTransform(tr)
                p.drawPath(symbol)

@pijyoi Thank you so much! This problem has bothered me for so long, your solution works perfectly.