Actually I think I meant if the diff eq was
'diff(y,x,2)+x^2*y=e*y
'diff(y,x,2)+x^4*y=e*y
I want to see the direction field of de/dx if that is possible.
Rich
------------Original Message------------
From: "Richard Hennessy"<rvh2007 at comcast.net>
To: "Walter Wegscheider" <walter.wegscheider at ph-noe.ac.at>, maxima at math.utexas.edu
Date: Fri, Jun-20-2008 1:18 PM
Subject: Re: [Maxima] Problems with plotdf
I am not having any bugs in plotdf yet but I have a different issue. I want to see the direction field of
'diff(y,x,2)+x^4*y=0 or 'diff(y,x,2)+x^2*y=0 but I don't understand the documentation so I can't figure out what to enter to get that.
Can anyone help?
Thanks,
Rich
------------Original Message------------
From: Walter Wegscheider <walter.wegscheider at ph-noe.ac.at>
To: maxima at math.utexas.edu
Date: Fri, Jun-20-2008 3:57 AM
Subject: Problems with plotdf
I have Problems with Direction Fields (Windows XP SP2, Maxima 5.15.0,
wxMaxima 0.7.5)
If I try to plot Inputs like (see Maxima Manual)
plotdf(x-y^2,[xfun,"sqrt(x);-sqrt(x)"],
trajectory_at,-1,3],[direction,forward],
[y,-5,5], [x,-4,16])$
including [xfun, ...] I always get failures - without xfun
everything is working fine.
Thanks and kind regards
Walter Wegscheider
Failure description in OpenMath:
Input file has syntax errors
can't read "_WinInfo.dfplot(nolegend)": no such element in array
while executing
"set _WinInfo[set win]($var)"
(procedure "oget" line 3)
invoked from within
"oget .dfplot nolegend"
invoked from within
"set nolegend [oget .dfplot nolegend]"
("uplevel" body line 1)
invoked from within
"uplevel 1 set $v \[oget $win $v\]"
(procedure "makeLocal" line 3)
invoked from within
"makeLocal $win c nolines nolegend plotpoints pointsize
bargraph linewidth"
(procedure "drawPlot" line 2)
invoked from within
"drawPlot $win [list $ans] -tags [list [concat $tags line[oget $win
curveNumber]]] -fill $color -label $label"
("foreach" body line 41)
invoked from within
"foreach {xvalues yvalues} [lrange $d 1 end] {
# puts "xvalues=$xvalues"
#puts "here:$curvenumber,[oget $win curveNumber]"
oset $win ..."
("xversusy" arm line 6)
invoked from within
"switch $type {
xversusy {
#puts "starting .. [oget $win curveNumber]"
set curvenumber [oget $win curveNumber]
# the data can be multiple l..."
(procedure "redraw2dData" line 13)
invoked from within
"redraw2dData $win -tags path"
(procedure "replotdf" line 24)
invoked from within
"replotdf $win"
(procedure "plotdf" line 28)
invoked from within
"plotdf -dydx "x-1.0*y^2" -xfun {sqrt(x);-sqrt(x)} -trajectory_at
{-1 3} -direction {forward} -ycenter {0} -yradius {5} -xcenter {6}
-xradius {10} "
("eval" body line 1)
invoked from within
"eval $inputdata"
_______________________________________________
Maxima mailing list
Maxima at math.utexas.edu
http://www.math.utexas.edu/mailman/listinfo/maxima
_______________________________________________
Maxima mailing list
Maxima at math.utexas.edu
http://www.math.utexas.edu/mailman/listinfo/maxima