small scatter plot markers in matplotlib are always black

Question

I\'m trying to use matplotlib to make a scatter plot with very small gray points. Because of the point density, the points need to be small. The problem is that the scatter()

Answer 1

If the marker has no face (cannot be filled, e.g. '+','x'), then the edgecolor has to be set instead of c, and lw should not be 0:

scatter([1,2,3], [2,4,5], marker='+', edgecolor='r')

The following will no work

scatter([1,2,3], [2,4,5], s=1,  marker='+', facecolor='0.5', lw = 0)

because the edge/line will not be displayed, so nothing will be displayed.