Oh, I didn't expect Racket to change and I think when you're teaching programming you can just say "this is how the language is." My question is what people might suggest for a system that's geared toward algebra help, not programming.
On Mon, Aug 6, 2012 at 6:18 PM, J. Ian Johnson <i...@ccs.neu.edu> wrote: > The identifier/number grammar is unlikely to change. If it really bugs you, > perhaps you can re-provide make-rectangular as c or complex and have students > write (complex real imag). You could also use @ notation and have them write > @complex[real imag]. > -Ian > ----- Original Message ----- > From: "Todd O'Bryan" <toddobr...@gmail.com> > To: "PLT-Scheme Mailing List" <us...@lists.racket-lang.org> > Sent: Monday, August 6, 2012 6:05:31 PM GMT -05:00 US/Canada Eastern > Subject: [racket] weirdness with complex numbers > > I just discovered that the way you enter (and display) a number like > > 1/2 + (2/3)i > > in Racket (and Scheme, presumably) is 1/2+2/3i. > > I understand why that is, and can't think of what else to do, but has > anyone had students get confused because the form looks like the i is > in the denominator of the imaginary part? > > What's more potentially confusing is that 1/2+2i/3 is a legal > identifier in its own right. > > I'm working on a program that models basic algebra in the way that > high school students are taught to do it, and one of my self-imposed > rules has been that "math should look like math." In other words, I'm > trying to minimize the conversion gymnastics that students have to put > up with when they enter math in calculators or computer programs. In > that spirit, I'm not sure if it would be better to allow the > inconsistency with the way order of operations normally works or just > have students enter 1/2+(2/3)i (or 1/2+2i/3, maybe) and do the > conversion behind the scenes. > > Anyone have any thoughts or prejudices one way or the other? > > Todd > ____________________ > Racket Users list: > http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
