A few days ago I spent a couple of hours getting PyObjC working with sage. The objective was to be able to write little sage-based GUI applications. (Though it could easily turn into a full-blown sage.app IDE, that was outside the scope of 2 hours playing around.)
The basic notion of PyObjC is that you can write your program in python, inheriting python objects from objective-c classes, and making your python data members accessible to objective-c. That makes the Cocoa libraries directly callable from sage. I wrote a little app to demonstrate one possibility. It takes from GUI fields a function, parameter names and a variable, and differentiates the function. It has three source files, two of which are boilerplate (one is a python file that sets up the path and initialises sage, the other is an objective-c file that starts the application). The third file is below with a couple of comments. A GUI screenshot is at http://alliance.anu.edu.au/access/content/group/hpv/public/differentiator.png #---------------- Code for GUI controller ---------------- #import the relevant parts of Cocoa from Foundation import * #import the relevant parts of Sage from sage.calculus import * from sage.calculus.var import * from sage.calculus.calculus import log, sin, cos #"controller" is the class that talks to both the GUI and Sage class controller(NSObject): # the three input fields are wired to the GUI text input fields functionInput = objc.ivar(u"functionInput") variableInput = objc.ivar(u"variableInput") parametersInput = objc.ivar(u"parametersInput") # the output field is wired to a GUI label calculatedDerivative = objc.ivar(u"calculatedDerivative") # the GUI "derivative" button triggers this method def doCalculation(self): # standard sage code, assuming that the inputs # are strings. # declare the symbolic parameters var(self.parametersInput) x = var(self.variableInput) # declare the function to differentiate f = eval(self.functionInput) # differentiate (this illustrates how 'standard sage' is available) f = f.derivative(x) # return the result to the GUI. self.calculatedDerivative = f.__repr__() #---------------- End of GUI controller code ---------------- About half of the 'couple' of hours was reading through the sage initialisation code and setting up the boilerplate files I referred above. The other half was because I suck at python... The weakness of this approach is that sage is running the main application loop. I.e. if f.derivative() takes its time, then there's a spinning beachball. I assume the big M's overcome this by separating their GUIs from their kernels. The big strength is much the same. Because sage is running the main application loop, you don't have to think about message passing of any sort. It should be easy enough to subclass NSView or something to display plots. Etc. If anyone's interested in kicking around ideas or explaining why this is a dumb idea, please go for it. If you want the boilerplate code you are welcome, but it was mostly hard hacks to get things working, and is utterly specific to my system. D ================================== David J Philp Postdoctoral Fellow National Centre for Epidemiology and Population Health Building 62, cnr Mills Rd & Eggleston Rd The Australian National University Canberra ACT 0200 Australia T: +61 2 6125 8260 F: +61 2 6125 0740 M: 0423 535 397 W: http://nceph.anu.edu.au/ CRICOS Provider #00120C --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
