Strange behaviour of 'saveas' function

I've a complex vector of 409600 elements. I do the scatterplot of the elements and then save as jpg image 600 x 800.

    % iq is the name of the vector
    figure('position',[1,1,800,600]);
    plot(imag(iq),real(iq),'r-*');
    title('SCATTERPLOT');
    saveas(gcf,'scatterplot.jpg', jpg);

The result is:

??? Error using ==> plot
Invalid first data argument

Error in ==> scatterplot at 121
    plot(yy, zeros(1,len_yy), plotstring);

Error in ==> print at 2
scatterplot(in,1,1,'k-o');

Error in ==> saveas at 154
        print( h, name, ['-d' dev{i}] )

Is very annoying because sometimes it works, sometimes doesn't; and I can't understand the reason. Plus, if I save in 'fig? format it always works.

saveas(gcf,'scatterplot','fig'):

Can somebody help me to solve this easy code??

Answer 1

[Image Analyst]

Have you tried the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_save_my_figure.2C_axes.2C_or_image.3F_I.27m_having_trouble_with_the_built_in_MATLAB_functions.

By the way, it's strange that the line it complains about

plot(yy, zeros(1,len_yy), plotstring);

is not in the code you posted. Why is that? What is line 121 of your scatterplot.m? Or actually, what is yy and len_yy there when it crashes there? Do you know how to use the debugger to set breakpoints and examine variables?

Answer 2

[Eugenio]

Hi Analyst, I don't know why during the execution Matlab goes execute scatterplot.m script. I usually test this kind of script on the workspace, and so I've never debugged it. I did it right now, and I've realized that I've created an m script called "print.m" that has benn called instead of "print.m" of graphic toolbox. So the code I've posted works only if i do not use the folder with my print.m as "Current Folder" path. Problem is near to be solved..thank you!