Geometry app three suggestions

[Alberto Candel]

(04-11-2014 10:57 PM)eried Wrote:  Hey Alberto thanks for sharing, can you elaborate what things made you use another geometry tool? I never used anything for geometry in school/university so I am a bit away from the field, but I thought these geometry tools were made for interacting "graphically" in the path of finding a numerical solution (like for example I always design small pieces in 3d to 3d-print and I always have to solve hidden angles of the objects, usually on a paper)

Does your suggestions replace the ones I suggested in the first post in "priority"? (from your view point)

Well, for me it was not about choosing one app over another. The course is Discrete and Computational Geometry, based on the book by Devadoss and ORourke with same title. The computational aspect of it is at the level of abstract algorithms, not actual implementation. I felt I was not competent enough to base it around the HP Prime, so whatever utilities I needed I felt more comfortable with Mathematica. Besides, Mathematica is readily available in our labs, and the course was being developed based on students interests and capabilities (we are not done yet).

But the Prime has lots of capabilities which could be made more obvious with some documentation from HP. True that there are lots of docs like HP Prime by Parisse but it would be nice to have an official hardcopy.

For example, just between my previous post and this one, I discovered that you can easily graph the convex hull of a set of points by going to the Geometry Symbolic view and typing, for example:

GH:=convexhull(1+3*i,1+9*i,1+11*i,3+6*i,4+9*i,6+6*i)
v GA:=polygon(convexhull(GH))

(v is the check mark)

and then go to Plot to view the convex hull. (This is related to exercise 4.7 in textbook above.) BTW, Mathematica complains when doing this hull.

Yes, I think our suggestions are aimed at different users, and I did not intend to replace yours; just thought to append a few others.

[parisse]

(04-11-2014 10:48 PM)Alberto Candel Wrote:  * Make the Geometry App more like the Computational Geometry Package in Mathematica. ConvexHull, Voronoi Diagram, Delaunay Triangulation should be readily available. There is a convex hull function in CAS, but it requires some extra programming to go from the list of points to the picture. I could not find Voronoi or Delaunay.

What do you mean by extra programming for convexhull? GC:=convexhull(list of points or complex); point(GC) will display the points and polygon(GC) will display the polygon.
I did not program Voronoi diagram nor Delaunay triangulation, but it should not be that hard to program it yourself in a CAS program if you need it.
By the way, I have no idea what the geometry package of mathematica looks like, I don't have a mathematica license:-)

Quote: * It should be possible to save a picture obtained on the Geometry App of the HP Prime as a PDF or EPS or something like that which then could be transfered to a PC or smart phone via Bluetooth (yes, the connectivity kit does not work in Linux). This capability would be great for preparing LaTeX docs for the course.

This could be easily done by exporting the SYMB view to a text file that you could transfer and load in Xcas where you can export your figure as PDF/EPS/PNG or translate to LaTeX. I think that supporting transfert of figures as text files to and from the PC would really be useful.

[Alberto Candel]

(04-12-2014 06:13 AM)parisse Wrote:  What do you mean by extra programming for convexhull? GC:=convexhull(list of points or complex); point(GC) will display the points and polygon(GC) will display the polygon.
I did not program Voronoi diagram nor Delaunay triangulation, but it should not be that hard to program it yourself in a CAS program if you need it.
By the way, I have no idea what the geometry package of mathematica looks like, I don't have a mathematica license:-)

Thanks. I was able to find convexhull in the time between my two previous posts. The Mathematica package essentially consists of Voronoi and Delaunay, and 3d versions. And lots of options!

Quote:This could be easily done by exporting the SYMB view to a text file that you could transfer and load in Xcas where you can export your figure as PDF/EPS/PNG or translate to LaTeX. I think that supporting transfert of figures as text files to and from the PC would really be useful.

Is there documentation about exporting the SYMB view?

[parisse]

It's unfortunately not implemented yet...

[Mic]

Two suggestions :
* translate geometry commands in the selected language
* display calculated variables and text on the drawing : EDIT : it is possible by checking in Num view.

[eried]

(04-15-2014 05:18 AM)Mic Wrote:  * translate geometry commands in the selected language

[parisse]

Why not?
I do that with Xcas (this is not limited to geometry), but unlike with the TI9x, the keywords are back-translated to English when the session is saved, so that you can use it on a PC configured with another language.
It's not essential, but it could help because when you are in highschool (or even later) you usually do not know the English words for geometric constructions (for example mediatrice is the French translation of perpendicular bisector).

[eried]

(04-15-2014 11:03 AM)parisse Wrote:  Why not?
I do that with Xcas (this is not limited to geometry), but unlike with the TI9x, the keywords are back-translated to English when the session is saved, so that you can use it on a PC configured with another language.
It's not essential, but it could help because when you are in highschool (or even later) you usually do not know the English words for geometric constructions (for example mediatrice is the French translation of perpendicular bisector).

But the translation in the prime itself is over the commands or just on the menus/GUI (and they resolve to english commands when inserting them)? Because I really think the command translation messes up the system forever. Look at Excel, it is a really well done app but it is so messed up keeping up with different translations for all locales, macros translate the commands back to english, you can't follow any online guide that does not uses your local language, etc.

[parisse]

In Xcas, you can always use the English keyword or the local keyword, both are recognized. As I already said, the session is stored using English keywords, therefore you can run it everywhere.

[eried]

That is why I asked, sounds like lots of problems to me. Just check our spanish translation in the prime. Our spanish students may end needing to type sphere to make a circle due the poor translation.

If the menu is wrong but the command is inserted in english, you can make at least the relation. I am just saying because I see this same issue in excel, help has several mistakes with commands due the same problem of the translation, after so many years and versions. Of course in english works perfect.

[parisse]

Maybe a problem specific to closed-source software. In Xcas, if there is a translation error, anyone can report it and modify the keywords file where the translations are stored (so that you don't have to wait for the next update to have the right translation).