cannot copy figure

I use MATLAB to plot figures very often. This is the very first time that I could not copy figure to clipboard. If I go back and open my old figures, I could copy it. But all today's figures cannot be copied. Sometimes I even got error message though not always:

??? Error using ==> print at 325
Invalid handle object.

Error in ==> editmenufcn at 76
            uimenufcn(hfig, 'EditCopyFigure')

I double-checked many times and it seemed that once I loaded a specific file (frequency_lifetime_PbTe.dat) then the figure could not be copied. So strange to me.

I copy one of my simple m-files here:

v1=load('frequency_lifetime_PbTe.dat');
x1=v1(:,1);
y1=v1(:,2); %ps
loglog(x1,y1,'bx','LineWidth',1);

Could anyone help me with this? Thanks a lot.

[Walter Roberson]

One thing I would check would be class(v1) . When you use that syntax for load, v1 would be prone to becoming a structure array. I personally do not recommend using load() for anything other than .mat files.

[Zhiting]

Thanks for your suggestion. I actually use load for other same format files as well and they all work. Even for this file, the figure can be plotted out, only encountered problems while copying figure.

[Walter Roberson]

Are any values in x1 or y1 negative or equal to 0 ?

[Zhiting]

No. Actually the figure was plotted out correctly. I guess just because the amount of data is too large. I have over 161994 rows in v1.

[Walter Roberson]

Hmmm, possibly. You could test by plotting subsets of the data to see if there is a particular maximum limit. And once you had found that limit, I would try changing the data for the next item and trying to plot including that data -- to see whether it is truly the number of items or if it is data dependent.