Re: saving initialization cells as a .m file

*To*: mathgroup at smc.vnet.net*Subject*: [mg99875] Re: saving initialization cells as a .m file*From*: "Sjoerd C. de Vries" <sjoerd.c.devries at gmail.com>*Date*: Mon, 18 May 2009 02:30:17 -0400 (EDT)*References*: <guj87p$hr4$1@smc.vnet.net>

Hi Baris, I think this is a Mathematica bug involving SuperDagger. SuperDagger[x] prints as an x with a superscripted dagger. When you type x ctrl-^ esc dg esc == SuperDagger[x] you get True. However, x ^ esc dg esc (without ctrl together with ^) prints as something very similar, but it isn't. Check the two for equality and you get False. Internally, the first one is represented as SuperDagger [x] and the second one as Power[x, \[Dagger]]. Now, the bug is that if you copy the real SuperDagger (x ctrl-^ esc dg esc) to a text file, it is stored as ^\[Dagger]. If this is read in on its turn it is interpreted as a dagger power which doesn't work. Mathematica should have copied it as SuperDagger[ ]. If I run the code directly as shown in your post I get the same error you are reporting. If I replace the dagger with the ctrl-^ version it works. So, the workaround is changing the f[t]^\[Dagger] part in your .m file in SuperDagger[f[t]]. I guess you should send in a bug report. Cheers -- Sjoerd On May 15, 10:13 am, Baris Altunkaynak <fractaldimens... at yahoo.com> wrote: > Hi, > > I have the following code which runs fine in a notebook: > > SuperDagger[A_List] := Conjugate[Transpose[A]] > eqn = {f'[t] == -f[t]^\[Dagger].f[t], f[0] == RandomReal[{0, 0.= 1}, {3, 3}]}; > NDSolve[eqn, f, {t, 0, 10}] > > but when I save the first two lines (definition of SuperDagger and eqn) i= n a .m file and load them with a Get command, although Mathematica loads th= e definitions, NDSolve doesn't like the input and complains that derivative= at t=0 is not defined. Weirdly if I copy and paste the output of NDSolve= and evaluate it, it runs fine. Do you know how can I fix this? > > best regards, > > Baris Altunkaynak