When opening old files with X-Y plots, I get spurious empty legend boxes in the plots.

Switching legend visibility off doesn't work, as soon as I click the canvas, the box re-appears. Copying the region to a new sheet (in version 8348) helps. There I can switch the legend off and it keeps off upon re-opening the file.

So a mitigation strategy would look like this:
- copy all content of the old file
- close the old file
- paste it into an empty new file
- switch off all the legends where required
- save the new file in place of the old one

Yet that doesn't work. If I copy all in one, the problem persists. My current hypothesis is that this might be some side effect of having too many plots or some malicious variable or whatever.

Can anyone reproduce this?


xyplot.sm (240kb) downloaded 27 time(s).

Five years ago, I changed the behavior of the legend. Since then, empty names hide elements of the legend. To return them, it is enough to have a space as the name.

Edited by user 11 August 2023 07:53:54(UTC)  | Reason: Not specified

Hello, the legends haven't been lost but have't been there in the original version. So the problem is not that the contents of the legend is lost but that empty legends appear without intent.

I produced the first issue of the Handbuch 9 years ago and it already had a section on XYplot (just looked it up in the SMath file manager). So, yes, the file is very old. It has been edited from time to time. In 2020, when I produced the last update, the images are ok, while now I faced the issue.

My guess is that at some point in time, the legend wasn't shown if all or some entries were empty. Perhaps you had to drop that logic when using empty entries to suppress the sample trace.
At least I am sure that I didn't deliberately switch on legends in all the plots without providing proper entries.

Yet I don't see what could be done about it, I just have to fix the legends in legacy files. Thanks for having a look at the issue.

I'd propose to make empty legends invisible. The help text for IsVisible could contain a hint, that if the legend should be visible, at least one trace name must not be empty.

So if one sets legend visibility to true but all trace names are empty, the names could be automatically populated with sensible names (e.g. a stringified version of the entry).

Also, in the name entry, a hint would be good that empty name removes the trace from the legend.

This function is already implemented in the plugin. With its help, sequential drawing of curve points occurs. The function returns sets of all detected curves consisting of a sequence of points.
The marching cubes algorithm generates a random set of pieces, I added a function for ordering them. This is necessary for high-quality printing of a PDF document. Now, when zoomed in, all lines do not contain artifacts.
The algorithm itself has not yet been optimized, but it is quite working, since no one has complained about the picture yet.

Even a regular graph can return a set of curves.

Edited by user 02 November 2023 19:38:01(UTC)  | Reason: Not specified

I found the reason for the problem. It is very simple. At the end of the file, I started experimenting with setprop and actually used setprop("XYPlot\002E\Legend\002E\IsLegendVisible",1). This seems to affect all plots with the name XYPlot (in the property settings), regardless if they are above or below the setprop command in the sheet. XYPlot happens to be the default name of all existing plots and setprop overrides any command from the settings dialog.