Can I change lines from numeric to datetime without deleting them?

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I have an already generated plot and I want to change the X data for all lines on the plot to some other data that happens to be datetimes (the original X values were numeric). When I do this, the lines on the primary Y seem to get converted ok, but when I have lines on a right Y, I am getting errors.
This simple script should demonstrate the issue:
% Create a figure
f = figure;
ax = axes(f);
% Initialize the right Y
% Plot something on the left
line1 = plot(ax,1:10,1:10);
% Plot something on the right
line2 = plot(ax,1:10,(1:10).^2);
% Make the left Y active again
% Change to datetime
% Some new x data
newX = datetime(2022,9,1:10);
% Set the XAxis ruler to be a datetimeruler
ax.XAxis =;
line1.XData = newX;
line2.XData = newX;
Line 1 will update as expected, but Line 2 still wants numeric data for some reason. I have already tried setting the XAxis after switching the active Y axis as well and that doesn't seem to change anything.
Is there a better/different way to easily switch between numeric and datetime data for all lines on a plot?
I know I could delete the lines and run plot again, but the real use case has quite a few lines and the size of the data is pretty large so not having to redraw them would be ideal.
Adam Danz
Adam Danz on 22 Sep 2022
If the options are mixed classes that require different axes types (e.g., numeric, categorical, datetime, duration), then it's better to just replace the line objects with new ones. Unless you're dealing with 100s of lines, the processing time won't differ noticeably between those two options.

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