Undefined function or method 'cmap' for input arguments of type 'double'

[EDIT: 20110602 04:54 CDT - reformat, clarify - WDR]

i get this error when i run the following commands

for i=1:n
prompt = {'Enter image name i:','Enter colormap name i:'};
title = 'Image display - assignin example';
lines = 5;
%def = {'my_image','hsv'};
answer = inputdlg(prompt,title,lines);
assignin('base','imfile',answer{1});
assignin('base','cmap',answer{2});
end

k= ones(5,2);
for i=1:5

k(i,1)=str2double(cmap(i));
k(i,2)=str2double(imfile(i));
end

this works fine when i run them , but when i put these commands in my GUI program (the prompt window is a part of the GUI) then i get the above error

i have been trying it for over 10 days now without a clue towards the problem, pls pls help me

thanks

Answer 1

[Walter Roberson]

I don't know what answer you are expecting. cmap and infile would be character strings after the inputdlg, and indexing a character string gets you a single character; why would you want to interpret those characters as individual doubles when your default answer suggests you are expecting something like 'hsv' as the string?

In any case, your problem is that when you are in a function, cmap and imfile are going to refer to the cmap and imfile variables of the function, not to the cmap and imfile that you assigned in to the base workspace. Add this before the "for" loop:

cmap = evalin('base', 'cmap');
imfile = evalin('base','imfile');

[sumeet]

THANK U WALTER

am new to MATLAB, and somehw have made a complex gui step by step just by experimenting with the software, so i lack the kind of simple common sense that u showed here

ur command works just fine and has solved my problem

thanks again

[sumeet]

there is another problem wid the above now, the matrix "k" is only taking the first digit of the number i input in the prompt. so i fi write "456" in the prompt box, then "k" only shows "4" for that element instead of showing " 456 "

[sumeet]

prompt = {'Enter image name:','Enter colormap name:'};

title = 'Image display - assignin example';

lines = 3;

%def = {'my_image','hsv'};

answer = inputdlg(prompt,title,lines);

assignin('base','imfile',answer{1});

assignin('base','cmap',answer{2});

cmap = evalin('base', 'cmap');

imfile = evalin('base','imfile');

% UIWAIT makes load_and_stress_calculation_CDF wait for user response (see UIRESUME)

% uiwait(handles.figure1);

k= ones(8,2)

for i=1:8

k(i,1)= str2num(cmap(i));

k(i,2)=str2double(imfile(i));

end

disp(k)