Output argument (and maybe others) not assigned during call to

Hello! I am getting the following error message when running this function:

Output argument "gfp_colormap" (and maybe others) not assigned during call to "gfp_colormap".

Error in globalmergedplot (line 15)   data_rgb =[data_rgb,ind2rgb(datos{n},gfp_colormap)];

When I simply replace my own colormaps (gfp_colormap and dapi_colormap) for some default colormaps of MATLAB (for example winter or spring) everything goes right.... Why the function does not recognize my colormaps (they work perfect out of this function)???. Any Ideas? Thanks in advanced!

 %MYFUNCTION:
 function globalmergedplot(datos)
 load gfp_colormap
 load dapi_colormap
 load red_colormap

 %CONVERTIMOS TODAS LAS IMÁGENES A RGB SEGÚN SU MARCADOR
 data_rgb={};
 for n=1:length(datos) 
    impar=mod(n,2)
    if impar==1
        data_rgb =[data_rgb,ind2rgb(datos{n},gfp_colormap)];
    else
        data_rgb =[data_rgb,ind2rgb(datos{n},dapi_colormap)];
    end
end

 %HACEMOS UN MERGE DE LOS CHANNELS DE TODAS LAS IMAGENES POR PAREJAS.
 data_merged={};
 for n=1:length(data_rgb) 
    impar=mod(n,2)
    if impar==1
        data_merged=[data_merged,imadd(data_rgb{n},data_rgb{n+1})];
    else
    end
 end

 %VISUALIZAMOS EL PLOT DE RESULTADO CON LA FUNCION IMDISP.
 output=figure(1),
 plot_merged=imdisp(data_merged,'Border',[0.01 0.01]);
 end

Answer 1

[Walter Roberson]

You are "poofing" variables into existence and that is confusing MATLAB.

This will not be fixed in MATLAB: MATLAB is deliberately moving towards making those situations errors.

To get around the problem, before your lines

 load gfp_colormap
 load dapi_colormap
 load red_colormap

add the lines

gpf_colormap = []; dapi_colormap = []; red_colormap = [];

That will force MATLAB to understand the names as being the names of variables,

[Stephen23]

Using function syntax rather than command syntax is a much better habit to learn and is totally unambiguous:

S = load(...);

Answer 2

[Stephen23]

Rather than magically making variables appear in the workspace, always load into an output variable:

S = load('gfp_colormap.mat');
...
S.gfp_colormap

Answer 3

[MARIA RODRIGUEZ SANZ]

Thank you very much for your help! Now it works perfect!