[Maxima-bugs] [ maxima-Bugs-1366253 ] plot2d(log(x),[x.-5,5])

[SourceForge.net <no...@so...>]

Bugs item #1366253, was opened at 2005-11-25 05:29
Message generated for change (Comment added) made by robert_dodier
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1366253&group_id=4933

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: Lisp Core - Plotting
Group: To be reviewed
>Status: Closed
>Resolution: Fixed
Priority: 5
Private: No
Submitted By: Nobody/Anonymous (nobody)
Assigned to: Nobody/Anonymous (nobody)
Summary: plot2d(log(x),[x.-5,5])

Initial Comment:
Using Maxima5.9.2

plot2d(log(x),[x.-5,5])
Result is a graph of the log(x)including a mirrored 
graph concerning the y-axis.
When i use wgnuplot.exe directly, this problem does not
occur.

----------------------------------------------------------------------

>Comment By: Robert Dodier (robert_dodier)
Date: 2007-06-27 14:35

Message:
Logged In: YES 
user_id=501686
Originator: NO

Just tried the plot_realpart flag in plot2d (both true and false, Windows
and Linux, openmath and gnuplot formats). In each case the result is as
expected. Closing this report as fixed.


----------------------------------------------------------------------

Comment By: Robert Dodier (robert_dodier)
Date: 2006-08-13 22:43

Message:
Logged In: YES 
user_id=501686

Code to modify plotting when function value is complex was
committed as r1.64 src/plot.lisp. 

I find with Maxima 5.9.3cvs

plot2d(log(x), [x, -5, 5], [plot_format, openmath]);
plot2d(log(x), [x, -5, 5], [plot_format, gnuplot]);

both show only the region [0, 5] and only one curve (it
appears to work for openmath as well as gnuplot). Jaime or
someone, can you verify that you also get only one curve in
each plot2d ? If so we can close this report as fixed.


----------------------------------------------------------------------

Comment By: Jaime E. Villate (villate)
Date: 2006-06-27 06:16

Message:
Logged In: YES 
user_id=28692

The previous behavior (plotting the real part when the
function gives a complex number) has now been changed.

plot2d(log(x),[x,-5,5]) will now only show the region
where the funtion gives real numbers (x>0).

However, the change has not been made for the openmath case.
I will work on it. I also think that if the user asks for a plot
from x=-5, to x=5, the domain should be shown exactly as that,
without being cut to x=0 to x=5.

----------------------------------------------------------------------

Comment By: Raymond Toy (rtoy)
Date: 2005-11-29 12:28

Message:
Logged In: YES 
user_id=28849

This is caused by plot2d plotting the realpart of the
function.  Not sure if that's what's wanted or not.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1366253&group_id=4933