January 2015 - Pharo-users - lists.pharo.org

Re: [Pharo-users] PostGIS in Pharo

by HernÃ¡n Morales Durand

2015-01-28 16:18 GMT-03:00 Esteban A. Maringolo <emaringolo(a)gmail.com>: > Sure, > > I'll collect georeferenced data in a mobile app, which I'll later have to > group each one according to whether they fall inside a certain polygon > (geopolitcal boundaries, like city, district, province, etc.). > I could also geocode the coordinate and store all that data (city, > district, province, etc.), and then just group by each of these. And then > I'll have to plot that data on a choropleth map. > > But I'm asking to know if somebody has somehow mapped smalltalk geometry > objects to the typical geometry object of PostGIS. Something like PGPoint, > PGPolygon, that can "translate" themselves from/to string literals. > > I don't know about PostGIS, but if you need boundary datasets there is GADM or GeoNames which may cover your needs. Recently I did a ST script to read from GADM using a dBase package. And you could query throug SPARQL too. HernÃ¡n

Jan. 28, 2015

Re: [Pharo-users] New book for Pharo :)

by HernÃ¡n Morales Durand

I see and appreciate your effort really, but there is no reason to hide NumericalMethods from the book announcement. I am trying to avoid what the Python community did with NumPy and SciPy which is a mess. HernÃ¡n 2015-01-28 16:16 GMT-03:00 stepharo <stepharo(a)free.fr>: > Hernan > > This is 8 months that I push didier to release it. I spent my week-end to > edit it. > So when you talk about respect use your energy th right way. > > Stef > > > > 2015-01-28 14:21 GMT-03:00 stepharo <stepharo(a)free.fr>: > >> Didier Besset offered his great book "Object-Oriented Implementation of >> Numerical Methods >> An Introduction with Smalltalk and Java" to the community. >> >> We would like to thank Didier Besset for his great book and for his gift >> of the source and implementation to the community. >> >> > This is indeed, great news. > > >> >> You can find >> â¢ Archive of the original book, with code in both Java and Smalltalk >> https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods >> >> >> https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods/blob/m… >> >> >> â¢ An abridged version of Didierâs book, without the Java >> implementation and reference; our goal is to make the book slimmer and >> easier to read. The implementation presented in this book is part of the >> SciSmalltalk library. >> >> > The implementation presented in his book is part of the NumericalMethods > library. > > You want to promote SciSmalltalk, then first respect others. > NumericalMethods could be part of SciSmalltalk, but it is the library where > code was originally released. > > Cheers, > > HernÃ¡n > > >

Jan. 28, 2015

Re: [Pharo-users] PostGIS in Pharo

by Esteban A. Maringolo

Sure, I'll collect georeferenced data in a mobile app, which I'll later have to group each one according to whether they fall inside a certain polygon (geopolitcal boundaries, like city, district, province, etc.). I could also geocode the coordinate and store all that data (city, district, province, etc.), and then just group by each of these. And then I'll have to plot that data on a choropleth map. But I'm asking to know if somebody has somehow mapped smalltalk geometry objects to the typical geometry object of PostGIS. Something like PGPoint, PGPolygon, that can "translate" themselves from/to string literals. I'm trying to avoid writing everything by hand in SQL. Regards! pd: I'm also considering using something like CartoDB for this task, which is a few levels of abstraction higher. Esteban A. Maringolo 2015-01-28 16:07 GMT-03:00 HernÃ¡n Morales Durand <hernan.morales(a)gmail.com>: > Can you comment what are you trying to do? > > HernÃ¡n > > > 2015-01-28 13:10 GMT-03:00 Esteban A. Maringolo <emaringolo(a)gmail.com>: > >> Is there anybody using PostGIS in Pharo? >> >> Regards! >> >> Esteban A. Maringolo >> > >

Jan. 28, 2015

Re: [Pharo-users] New book for Pharo :)

by stepharo

Hernan This is 8 months that I push didier to release it. I spent my week-end to edit it. So when you talk about respect use your energy th right way. Stef > > > 2015-01-28 14:21 GMT-03:00 stepharo <stepharo(a)free.fr > <mailto:stepharo@free.fr>>: > > Didier Besset offered his great book "Object-Oriented > Implementation of Numerical Methods > An Introduction with Smalltalk and Java" to the community. > > We would like to thank Didier Besset for his great book and for > his gift of the source and implementation to the community. > > > This is indeed, great news. > > > You can find > â¢ Archive of the original book, with code in both Java and > Smalltalk > https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods > > https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods/blob/m… > > > â¢ An abridged version of Didierâs book, without the Java > implementation and reference; our goal is to make the book slimmer > and easier to read. The implementation presented in this book is > part of the SciSmalltalk library. > > > The implementation presented in his book is part of the > NumericalMethods library. > > You want to promote SciSmalltalk, then first respect others. > NumericalMethods could be part of SciSmalltalk, but it is the library > where code was originally released. > > Cheers, > > HernÃ¡n >

Jan. 28, 2015

Re: [Pharo-users] PostGIS in Pharo

by HernÃ¡n Morales Durand

Can you comment what are you trying to do? HernÃ¡n 2015-01-28 13:10 GMT-03:00 Esteban A. Maringolo <emaringolo(a)gmail.com>: > Is there anybody using PostGIS in Pharo? > > Regards! > > Esteban A. Maringolo >

Jan. 28, 2015

Re: [Pharo-users] New book for Pharo :)

by HernÃ¡n Morales Durand

2015-01-28 14:21 GMT-03:00 stepharo <stepharo(a)free.fr>: > Didier Besset offered his great book "Object-Oriented Implementation of > Numerical Methods > An Introduction with Smalltalk and Java" to the community. > > We would like to thank Didier Besset for his great book and for his gift > of the source and implementation to the community. > > This is indeed, great news. > > You can find > â¢ Archive of the original book, with code in both Java and Smalltalk > https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods > > https://github.com/SquareBracketAssociates/ArchiveOONumericalMethods/ > blob/master/NumericalMethods/2015-Jan-WholeBookST-Java.pdf > > > â¢ An abridged version of Didierâs book, without the Java > implementation and reference; our goal is to make the book slimmer and > easier to read. The implementation presented in this book is part of the > SciSmalltalk library. > > The implementation presented in his book is part of the NumericalMethods library. You want to promote SciSmalltalk, then first respect others. NumericalMethods could be part of SciSmalltalk, but it is the library where code was originally released. Cheers, HernÃ¡n

Jan. 28, 2015

Re: [Pharo-users] Building 3D shapes in Roassal with interaction. Unexpected behaviour?

by Ronie Salgado

Hello Nicolas, Thanks for pointing this bug. I just fixed it in Woden-Core-RonieSalgado.64 . Can you try again? Greetings, Ronie 2015-01-28 10:40 GMT-03:00 Nicolas Lusa <nicolas.lusa(a)usi.ch>: > v := RWView new. > > e := (RWPyramid new) element. > e on: RWMouseButtonDown do: [ :ev | > ev element shape color: WDColor blue. > ev element changed. > ]. > v add: e. > > g := (RWCube new) element. > g on: RWMouseButtonDown do: [ :ev | > ev element shape color: WDColor green. > ev element changed. > ]. > g translateBy:(WDVector3 newX: 4.0 y: 0.0 z: 0.0). > v add: g . > > f := (RWCylinder new) element. > f on: RWMouseButtonDown do: [ :ev | > ev element shape color: WDColor red. > ev element changed. > ]. > f translateBy:(WDVector3 newX: 2.0 y: 0.0 z: 0.0). > v add: f. > > v addInteraction: RWMouseKeyControl. > v camera position: (WDVector3 x: 0.0 y: 0.0 z: 3.0). > v open. >

Jan. 28, 2015

Re: [Pharo-users] Why single inheritance?

by Cameron Sanders

Laura, Obviously, I should have let the experts answer, and I did not answer all of your questions in that last quick-off-the-cuff diss-the-strongly-typed-languages answer. My apologies. For me, i like to keep the namespace clean. And one must admit, with multiple inheritance, things can get confusing, and in some cases, the wrong methods come into play. If one breaks free of inheritance as a means to gain polymorphism, code re-usability can grow considerably, and the ability to substitute classes to be used by a 3rd party libraries grows with it. I generally prefer delegation(/decoration) approaches to inheritance, in part just to control the namespace and "interface" of a class. Traits are still not widely available in different smalltalks, are they? -Cam On Wed, Jan 28, 2015 at 10:41 AM, Laura Risani <laura.risani(a)gmail.com> wrote: > Hi all, > > What is the explanation why Smalltalk designers preferred single > inheritance+traits to multiple inheritance? Why is the former better than > the latter? > Do traits let you share state also or only behavior? > > Best, > Laura >

Jan. 28, 2015

Re: [Pharo-users] Why single inheritance?

by Cameron Sanders

Because smalltalk methods require so little code that overt-delegation is both easy to author and to understand. If on the other hand, one needs to repeatedly tell the compiler what types of data shall be used used, and then insert numerous delimiters, such delegation becomes onerous... and ... then one would beg for a compiler solution. -cam On Wed, Jan 28, 2015 at 10:41 AM, Laura Risani <laura.risani(a)gmail.com> wrote: > Hi all, > > What is the explanation why Smalltalk designers preferred single > inheritance+traits to multiple inheritance? Why is the former better than > the latter? > Do traits let you share state also or only behavior? > > Best, > Laura >

Jan. 28, 2015

Re: [Pharo-users] Why single inheritance?

by Damien Pollet

Mostly, multiple inheritance is difficult to implement well in a simple enough form. The only language I know of that has a reasonably usable version of it is Eiffel (probably Nit too, but I don't know enough about it http://nitlanguage.org) There is the diamond inheritance problem, the problem that inheritance (even in Smalltalk) mixes subtyping (interface extension) and reuse of implementation, problems of how to linearize method lookup, etc. On 28 January 2015 at 16:41, Laura Risani <laura.risani(a)gmail.com> wrote: > Hi all, > > What is the explanation why Smalltalk designers preferred single > inheritance+traits to multiple inheritance? Why is the former better than > the latter? > Do traits let you share state also or only behavior? > > Best, > Laura >

Jan. 28, 2015