Why Saveas appaer a error sometimes

Hello I try to use "Saveas" to save figure. However it's working some time and sometime a error appear :

Error using savefig (line 41) Argument must be a .fig file

Error in saveasfig (line 6) savefig(h, name);

Error in saveas (line 140) feval( ['saveas' format], h, name )

Error in Plot_Integration_Time (line 215) saveas(H,[path_res 'Delta Tension (V) At 5V and ' num2str(Frequency) 'HZ'],'fig');

I don't unterstand why it's not working. Because H is a figure.

a part of my code :

    H=figure;

    plot(Wait_time(Delta_Ind_5V_1s),Delta_Tension(Delta_Ind_5V_1s),'-xc',...
        Wait_time(Delta_Ind_5V_2s),Delta_Tension(Delta_Ind_5V_2s),'-xr',...
        Wait_time(Delta_Ind_5V_3s),Delta_Tension(Delta_Ind_5V_3s),'-xg',...
        Wait_time(Delta_Ind_5V_4s),Delta_Tension(Delta_Ind_5V_4s),'-xb',...
        Wait_time(Delta_Ind_5V_5s),Delta_Tension(Delta_Ind_5V_5s),'-xk',...
        Wait_time(Delta_Ind_5V_1s),Warning(Delta_Ind_5V_1s),'xc',...
        Wait_time(Delta_Ind_5V_2s),(1.5*Warning(Delta_Ind_5V_2s)),'xr',...
        Wait_time(Delta_Ind_5V_3s),(2*Warning(Delta_Ind_5V_3s)),'xg',...
        Wait_time(Delta_Ind_5V_4s),(2.5*Warning(Delta_Ind_5V_4s)),'xb',...
        Wait_time(Delta_Ind_5V_5s),(3*Warning(Delta_Ind_5V_5s)),'xk');
    xlabel('N° of Time Integration (-)');
    ylabel('Delta Tension (V)');
    title(['At 5V and ' num2str(Frequency)]);
    legend('1s','2s','3s','4s','5s','Warning 1s','Warning 2s','Warning 3s','Warning 4s',...
        'Warning 5s','location','Best');
    grid on;
    saveas(H,[path_res 'Delta Tension (V) At 5V and ' num2str(Frequency) 'HZ'],'fig');

If somebody could help me ;)

Thank you

Bastien

Answer 1

[Bruno Pop-Stefanov]

Can you try with something more simple, like

savesas(gcf, 'myfigure.fig')

?

Does the figure save correctly if you do it manually in the figure window (File > Save...)?

[Bastien]

Yes savesas(gcf, 'myfigure.fig') save correctly and the manually way to

actually my code works sometime but for some mesure it's doesn't work.

Answer 2

[dpb]

   saveas(H,[path_res 'Delta Tension (V) At 5V and ' num2str(Frequency) 'HZ'],'fig');

Your filename contains embedded blanks. If you insist on using such, you must enclose them in the double-quotes (") to keep it as a single string throughout the intermediate code.

fn=['"' path_res 'Delta Tension (V) At 5V and ' num2str(Frequency) 'HZ"'];
saveas(H,fn,'fig');

perhaps altho you don't show what path_res definition is. Perhaps also fullfile might be of use here.

[Bastien]

it's not working How path_res is create :

begin_date = datestr(clock);
date_string=begin_date;
date_string(12)='-';
date_string(15)='h';
date_string(18)='m';
date_string=date_string(1:17)
path_res=[num2str(Frequency),'HZ\',date_string,'\'];
mkdir(path_res);

[Image Analyst]

Why do you add an m at element 18, just to crop it off immediately afterwards in the next line? Maybe try adding a drive letter, or any first part of the path that is missing, might work.

[dpb]

A) Return and check error status

B) Step thru w/ debugger and ensure strings are valid.

C) Which OS? '\' is valid only for Windows I think???

C) You are intending to build multi-level directory structure here?

I'm guessing it's failing 'cuz of either an already existing path left over from a previous failed test or run or mis-specified path somewhere. Always check returns for success on such stuff so you know where it first went south. The problem may have come way back when so backtracking is much harder if so...

ADDENDUM

You're making awfully complicated file names--that leaves a lot of room for accidentally creating one that isn't valid somehow if a variable isn't what you expect. Particularly I'm wondering about your num2str portion perhaps being a floating point representation? Not sure what that would do to a file name otomh, but it wouldn't be pretty at best.

I'd suggest at least while debugging to build the file name as a separate variable and echo it to the command window so you see what it is and which ones succeed and fail when it happens. That should shorten the debug time significantly.

I'd still also suggest simplifying your naming scheme significantly and getting rid of the spaces--my experience has been they're fraught w/ difficulties to ensure always handled programmatically. It's an abomination M$ should've never introduced.

[Image Analyst]

Good points by dpb. I also recommend use of fullfile() to build full pathnames, and sprintf() to create the base file name. I never use that num2str() method and always use sprintf() instead.

Also, using forward slash for all operating systems works fine. Windows has no problem with forward slashes - it doesn't have to be a backslash, which can sometimes be a problem in sprintf() where you have to use \\ if you want a single \.

Click here for the debugging tutorial

Answer 3

[Any Moose]

Make sure there are no '.' in your filenames. Otherwise Matlab may try to save it as a filetype of .5Hz.fig; which won't work!

fn = replace(fn,".","-")