On Sep 1, 2009, at 8:58 PM, William Cauchois wrote: > It seems to me that the error comes from feeding a function which uses > i into fast_float (called by the plotting functions to compile the > function to be plotted into an optimized form). I tried a simpler > function using i and got the same error: > > sage: plot3d(x + y + i, (x, 0, 1), (y, 0, 1)) > Traceback (click to the left for traceback) > ... > TypeError: float() argument must be a string or a number > sage: from sage.ext.fast_eval import fast_float > sage: fast_float(x + i, 'x') > Traceback (click to the left for traceback) > ... > TypeError: float() argument must be a string or a number > > It would make sense for the low-level representation used by > fast_float not to include a concept of imaginary numbers. Have you had > success plotting any other functions that use imaginary numbers? There > should be a mechanism to fall back to using the unmodified function in > the event that fast_float fails to convert the function.
The code leaves a lot to be desired. For example, now that we have fast_callable, with CDF support, we should be using that. Actually, we're using the helper function setup_for_eval_on_grid (to normalize the boundaries) and then ignoring the returned function, so this check is completely useless. As for being a function of one or two variables, it's unclear what the best approach is to take here. Clearly we want to allow plotting complex functions of a complex variable, but the alternative is useful too. For functions, the number (and names) of the arguments they take is explicit, but for expressions like sin(z) or x+y+i it's not as obvious. Does the x in plot3d(x+1, ...) stand for the real part of the complex argument, or the entire thing? Or perhaps the bounds should be complex numbers defining the rectangle, like sage: plot3d(exp(z), (z, -1-i, 1+i)) though I'm not sure I like this notation either. - Robert --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
