I have now fixed the problem with the arrow and added square brackets as endpoints. While testing it I found a few additional errors with the endpoints that I have fixed as well. You can find it in the beta version of Graph:
http://padowan.dk/graph/DownloadBeta.php

Regarding square brackets, our textbook likes to use them for closed endpoints on a number line. I think most people may just use a circle that's not filled in.

Thanks again,

RVernon

(BTW, I wish that Graph also had square brackets for endpoints, in addition to the curved ones.)

I have never seen sqaure brackets used, but it should be easy to implement.

That is unfortunetely much more difficult to implement, but I will take a look at it when I find the time.

This is clearly a bug. I wonder why I never noticed it before. I will start fixing this imediately.

When teaching our students we pay particular attention to whether the ends of lines have closed circles, open circles or arrows. (BTW, I wish that Graph also had square brackets for endpoints, in addition to the curved ones.)

New feature request:
(1) Add Endpoints Start: and End: functionality to Insert Relation dialogue for example when graphing x=y^2 or x=abs(y)
(2) Fix the Parametric function dialogue so that when graphing {x(t)=t^2, y(t)=t} or {x(t)=abs(t), y(t)=t} the arrow for Endpoint Start points in the correct direction. It seems that you would need to add a left-pointing arrow to the right-pointing one that you already have. (BTW, choosing the open endpoint (curve) stays the same even after changing in the dialogue.

I could probably get the graphs I'm looking for by combining graphs, but this would be easier, especially when I show graphs interactively to my students in class (e.g., when doing transformations, etc.)

Whatever you decide to do, you've got a great program. Thanks.

RVernon