Re: display of graphics primitives

*To*: mathgroup at smc.vnet.net*Subject*: [mg101275] Re: display of graphics primitives*From*: David Bailey <dave at removedbailey.co.uk>*Date*: Sun, 28 Jun 2009 23:31:58 -0400 (EDT)*References*: <h1sv5e$mbi$1@smc.vnet.net>

dsmithy wrote: > Why do you have to place graphics primitives in the Graphics[ ] > expression in order for them to be displayed graphically? Why doesn't, > for example, Circle[ ] display as a graphic in StandardForm? Why must > it be Graphics[Circle[ ]]? > Thank you. > I think the real point here is that primitives are not really much use, except in combination - I mean suppose you output a circle at coordinates (3,4) what does that mean if you don't have other primitives, each with their own coordinates? If Circle[...] displayed as a circle, it would actually be a hindrance because you could not examine graphics expressions except in InputForm. It is often handy to take a graphics object g (say) and display its contents, e.g. by executing g[[1]] or f@@g David Bailey http://www.dbaileyconsultancy.co.uk