# LocusEquation is a circle, not an ellipse

Tang Dashi shared this question 6 years ago

I make an ellipse with Locus Command, but the LocusEquation command give me a circle.

(see attached file , red color).

Is there something I do not use the command correctly ?

Win10, desktop, Geogebra 5.0.0332.

Try

1

1. Works only for a restricted set of geometric loci, i.e. using points, lines, circles, conics.

you use a number s so the answer is wrong

1

The problem exists when I do not use numer s.

see file:

1

As far as I know LocusEquation command is still under development.

LocusEquation's version using boolean condition only works if your boolean condition involves equality of distances (not sums or differences) or paralelism or perpendicularity conditions.

If you want to draw an elipse using LocusEquation you achive it by using a different method for construction method. See attached file.

1

Thank you, cfleitas.

I have followed your method, I did not get a curve. But when I saved and reopened, the curve was showed!

maybe it was not so robust.

1

Hi, tried with as many geometric objects as possible

https://www.geogebra.org/m/XjWncYjP

1

for hyperbola, the equation problem also exists.

is there a bug?

1

Try

1

hello

I advice you to use only free points, lines, circles and generally free objects initially. hide the axis ( they are like numbers). use segment[point,point] nor distance[point,point]. then only clicks in menu and screen until locusequation[] command

here is your construction with these methods

saludos

Files: foro.ggb
1

@mathmagic, @Michel Iroir, @cfleitas

Thank you all.

as I tested: use "Distance" error; use "Segment" ok!

and the C,D must be free points.

see attached file.

I am curious about the difference between "distance" and "segment". (as for Circle, they are the same. but for locusEquation, there are different).