How to avoid ^- in maxima output? (Leo Butler) [Martin Kraska]
Subject: How to avoid ^- in maxima output? (Leo Butler) [Martin Kraska]
From: Martin Kraska
Date: Thu, 31 Oct 2013 22:17:10 +0100
Leo,
indeed the approach has solved the problem. It also inspired the solution of a similar problem with expressions of type a^b^c.
I suppose, we are not compatible to GPLv2, as we do not make any particular license statement and the base program SMath is closed source and we are bundling our stuff with SMath (plugin distribution is via the SMath extension manager).
Currently, we distribute the files smath.mac and smath.lisp together with the plugin and place them in the install dir of SMath (which is not really nice).
Having them in the Maxima installation would be fine for us. We would then load them from our init files. This, however would be problematic with existing Maxima installations, as there is no convenient Maxima update procedure (at least under windows).
Do you see any clean way to handle that?
Martin Kraska
> -----Urspr?ngliche Nachricht-----
> Von: Leo Butler [mailto:l_butler at users.sourceforge.net]
> Gesendet: Donnerstag, 31. Oktober 2013 14:55
> An: Martin Kraska
> Cc: l_butler at users.sourceforge.net; maxima at math.utexas.edu
> Betreff: Re: AW: [Maxima] How to avoid ^- in maxima output? (Leo Butler)
>
> > From: Martin Kraska <kraska at fh-brandenburg.de>
> > CC: <maxima at math.utexas.edu>
> > Date: Thu, 24 Oct 2013 18:05:04 +0200
> >
> > Leo,
> >
> > thanks a lot for the great help.
> >
> > I did not examine the code yet but I see that this might be the solution of
> > the given problem and I am glad to see that such problems can be handled
> on
> > the Maxima side. We would like to avoid any modification of existing
> Maxima
> > installations and rather load the scripts from our plugin directory. I guess
> > that the search path for maxima can be extended accordingly.
> >
> > Best regards, Martin
>
>
> Martin, sorry for the delay in replying, my outbound email server has been down
> for a while.
>
> I don't know if your project has found the code that I wrote useful. If so, and you
> wish to use it to provide a plugin to Maxima, then there is the issue of
> distribution. I do not know if your licensing is compatible with GPLv2. If it is,
> then please distribute the code with your plugins. If it is not *or* you are
> unsure (and I suspect this is the case), then the code can be added to Maxima
> under the share/contrib directory where it will be distributed under GPLv2.
>
> Regards,
> Leo
>
> >
> > > -----Urspr?ngliche Nachricht-----
> > > Von: Leo Butler [mailto:l_butler at users.sourceforge.net]
> > > Gesendet: Donnerstag, 24. Oktober 2013 16:48
> > > An: Martin Kraska
> > > Cc: maxima at math.utexas.edu
> > > Betreff: Re: [Maxima] How to avoid ^- in maxima output? (Leo Butler)
> > >
> > > > From: Martin Kraska <kraska at fh-brandenburg.de>
> > > > Date: Thu, 24 Oct 2013 01:09:02 +0200
> > > >
> > > > Leo, thanks for the response ( and Robert, for your's as well).
> > > >
> > > > Other examples are
> > > >
> > > > "e^-cos(x)/b", misunderstood as e^{-cos(x)/b},
> > > > "e^-c/b" , misunderstood as e^{-c/b}
> > > >
> > > > 1d versions which would be understood correctly, are:
> > > > "e^(-cos(x))/b"
> > > > "e^(-c)/b"
> > > >
> > > > Thus, how can Maxima be forced to bracket the unary minus operator in
> > 1d
> > > > output?
> > >
> > > Ok, I do see what you want. My suggestion is basically what RJF and
> Robert
> > > were hinting at. What you can do is use Maxima's ability to apply
> > > transformation rules to expressions to re-write the expression before it
> > is
> > > displayed. Here is what I mean:
> > >
> > > (%i10) (to_mx_display(), kill(all), load("smath.mac"))$
> > >
> > > (%i1) [e^-4, %e^-t/d, %e^-cos(x)/y];
> > > (%o1) [1/e^4,%e^-t/d,%e^-cos(x)/y]
> > >
> > > (%i2) to_sm_display();
> > > (%s2) %s <-- change outchar for different
> > display mode
> > >
> > > (%i3) [e^-4, %e^-t/d, %e^-cos(x)/y];
> > > (%s3) [e^{-4},%e^{-t}/d,%e^{-cos(x)}/y] <-- desired output
> > >
> > > (%i4) to_mx_display();
> > > (%o4) %o <-- revert to maxima's standard
> > 1d display
> > >
> > > (%i5) %s3;
> > > (%o5) [1/e^4,%e^-t/d,%e^-cos(x)/y] <-- the expr in %s3 is valid
> > maxima
> > > code
> > >
> > > where
> > >
> > > smath.mac:
> > > /* -*- Mode: maxima; Package: MAXIMA -*- */
> > > /*
> > > ;; Copyright Leo Butler (leo.butler at member.fsf.org) 2013 ;; Released under
> > the
> > > terms of GPLv2 */
> > >
> > > matchdeclare([sm_x],true,sm_y,lambda([e],if is(numberp(e) and e<0 and
> > e#-1)
> > > or is(not(atom(e)) and op(e)="-") then true else false));
> > > defrule(sm_exp_to_power,sm_x^sm_y,sm_x^{sm_y});
> > > sm_rules:['sm_exp_to_power];
> > >
> > > load("smath.lisp")$
> > >
> > > /* end of smath.mac */
> > >
> > >
> > > smath.lisp:
> > > ;; -*- mode: lisp -*-
> > > ;; Copyright Leo Butler (leo.butler at member.fsf.org) 2013 ;; Released under
> > the
> > > terms of GPLv2
> > >
> > > (in-package :maxima)
> > >
> > > (defvar *displa* (symbol-function 'displa)) (defvar *maxima-outchar*
> > $outchar)
> > > (defvar *smath-outchar* '$%s) (defvar $sm_rules)
> > >
> > > (defun $smath_displa (form &optional (sm-rules $sm_rules))
> > > "Display FORM by APPLY1-ing the rules in SM-RULES to the EXPR in
> FORM."
> > > (declare (special $sm_rules *alt-display1d*))
> > > (let ((rules (cdr sm-rules))
> > > (*alt-display1d* nil)
> > > (expr (third form)))
> > > (funcall *displa*
> > > (list (first form) (second form)
> > > (dolist (rule rules expr)
> > > (setf expr (mfuncall '$apply1 expr rule)))))))
> > >
> > > (defun $to_sm_display ()
> > > "Set-up Maxima to use SMATH_DISPLA to display output."
> > > (declare (special *alt-display1d* $outchar *smath-outchar*))
> > > (setf *alt-display1d* (symbol-function '$smath_displa))
> > > (setf $outchar *smath-outchar*))
> > >
> > > (defun $to_mx_display ()
> > > "Return Maxima to use standard DISPLA for 1d output."
> > > (declare (special *alt-display1d* $outchar *maxima-outchar*))
> > > (setf *alt-display1d* nil)
> > > (setf $outchar *maxima-outchar*))
> > >
> > >
> > > ; end of smath.lisp
> > >
> > > Leo
> >