Prloblem in labeling in SNAP and Matlab

Dear all,
I really am in trouble regarding this issue. I did classification by RF classifier in SNAP and classes were labeled by 0, 1, 2, 3, 4, 5, 6, 7 and (-1) was ‘no data’.

I transferred result in Matlab in tif format and ‘no data’ had ‘-1’ value. I visualized tif image in gray value by this code:

A= imread(‘myimage.tif’);
figure
I = imshow(A,[-1 7]);

and it was OK but I tried to get colorful image in Matlab but I have some problems with it:

Myimage in tif was ‘6081x9570 int16’

then I used below code in Matlab:

A= imread(‘myimage.tif’);
b = double(A);
b(b == -1) = NaN;

mymap = [

% 0 values in SNAP
0.4940 0.1840 0.5560

% 1 values in SNAP
0.0000 1.0000 1.0000

% 2 values in SNAP
0 0 1.0000

% 3 values in SNAP
0.0000 1.0000 0.0000

% 4 values in SNAP
1.0000 0.0000 1.0000

% 5 values in SNAP
1.0000 0.0000 0.0000

% 6 values in SNAP
0.0000 0.0000 0.0000

% 7 values in SNAP
1.0000 1.0000 0.0000

% ‘-1’ values that I converted to ‘NaN’ in SNAP
0.2500 0.2500 0.2500

];


rgb=ind2rgb(b,mymap);

figure,imshow(rgb)

but I do not know why my colourful map does not show ‘1 values ’ (I mean % 1 values in SNAP
0.0000 1.0000 1.0000). I do not not what is the problem? Is it coming from SNAP or code?