How to write annotation outside the drawing in data coords

Question

My graphic goes from y=-1 to y=10

I want to write a small piece of text in an arbitrary position, say at x=2000, y=5:

ax.annotate('MgII', xy=(2000.0, 5.0),  xycoords='data') 

Now I want the same, but this time the piece of text must be outside the graphic, but in the exact position I mark in data coordinates:

ax.annotate('MgII', xy=(2000.0, 10.5),  xycoords='data') 

But it then disappears (remember my graphic goes from -1 to 10). There is plenty of space free on top of the graphic.

And, if I specify

xy=(2000.0, 9.999) 

then the label appears nearly where I want it, only it is too close to the top border of the picture. I want it at y=10.5, specifically.

Answer 1

ax.annotate('MgII', xy=(2000.0, 10.5), xycoords='data', annotation_clip=False) 

By default in data units the annotation is only drawn if it is in axes.

You might be better off using a blended transform:

 trans = ax.get_xaxis_transform() # x in data untis, y in axes fraction  ann = ax.annotate('MgII', xy=(2000, 1.05 ), xycoords=trans)