Plots that Show Integer Points Only

Richard A Chandler shared this question 3 years ago

Is there a way I can make a plot that shows only integer points, like (2,3), and not any other points, where the coordinates might be other numbers, like (5/2,pi)?

The particular problem I'm trying to illustrate involves order relations on the set Z (integers). The relation is xy>=1. See the attached file. I can plot the hyperbola xy=1, or the inequality xy>1, which shows up as two shaded regions. But is there a way I can ask Geogebra to plot just the points with integer coordinates that are in those shaded regions?

Any help will be appreciated.

1

@Noel: trick needed so it works online eg

```If(IsDefined(C1), C1, (0, 0))
```
as Corner() returns (?,?) when the file is loading

1

I think you get problems with KeepIf(Sequence(Corner(... if Corner = (?,?)

1

Thanks for your help. I was able to accomplish what I wanted.

I feel a need for more information on the "corner" and "flatten" commands. What exactly do they do, and how do they produce the effect I see?