Python 3.3 pyqtgraph can't plot points
Question: Is it me, or is it impossible to plot points (scatterplot) in pyqtgraph using
Python 3.3?

I have quite big data*, and find matplotlib way too slow, so I would like to
give this a try:

1) `pyqtgraph.plot([1],[1])` shows nothing in the plot.

2) `pyqtgraph.plot([1,2,3,4], [1,2,3,4])` shows a line connecting the dots

3) `pyqtgraph.plot([1,2,3,4], [1,2,3,4], pen=None)` as suggested by docs,
errors**

4) `pyqtgraph.ScatterPlotItem()` does not exist.

I do not know what to try anymore... Did anyone get this working and would be
willing to share code?

* * *

* I am aware of the irony with the data I present, forgive me.

** TypeError: unsupported operand type(s) for -: 'NoneType' and 'NoneType'.

*** Perhaps unrelated, but I also can't get the examples to run (Ubuntu
13.04).


Answer: The correct ways to create a scatter plot are either by specifying the symbol
properties when plotting (symbol, symbolPen, symbolBrush, symbolSize; see the
[PlotDataItem
API](http://pyqtgraph.org/documentation/graphicsItems/plotdataitem.html#pyqtgraph.PlotDataItem.__init__)):

    
    
    pg.plot([1,2,3,4], [1,2,3,4], pen=None, symbol='o')
    

Or by directly creating a ScatterPlotItem, which seems to exist on my end:

    
    
    >>> import pyqtgraph as pg
    >>> pg.ScatterPlotItem
    <class 'pyqtgraph.graphicsItems.ScatterPlotItem.ScatterPlotItem'>
    

See `examples/ScatterPlot.py` on how to use the latter method.

