VERTCAT error when trying to populate array

Hi folks,

I am trying to write some fata into an array, which I will then write to excel. I get the VERTCAT error when trying to create the array (Error using vertcat Dimensions of arrays being concatenated are not consistent).

Can you help identify why this is please?

Each column of data should be 256 elements long.

My code is as follows:

headings = {'Pixel Value', 'R', 'G', 'B', 'Grey'};
pixelValue = (0:255)';
allCoke_R = imhist(allCokeMask(:,:,1));
allCoke_G = imhist(allCokeMask(:,:,2));
allCoke_B = imhist(allCokeMask(:,:,3));
allCokeGrey = imhist(rgb2gray(allCokeMask));
dataCollectionAllCoke = zeros(257, 5);
dataCollectionAllCoke = [headings; pixelValue, allCoke_R, allCoke_G, allCoke_B, allCokeGrey];
writecell(dataCollectionAllCoke, resultsPath, 'Sheet', nameStringExcel, "Range", 'A1'); 

Answer 1

[Jonas]

try putting {} around the second line of concatenation

dataCollectionAllCoke = [headings; {pixelValue, allCoke_R, allCoke_G, allCoke_B, allCokeGrey}];

or convert all variable entries to cells

dataCollectionAllCoke = [headings;num2cell([pixelValue, allCoke_R, allCoke_G, allCoke_B, allCokeGrey])];

both should work concerning the concatenation, but i am not sure about the needed format for the writematrix() command

[Teshan Rezel]

Hi, thanks for this! It seems to have gotten rid of the error. However, I am now getting the following output in the excel file, instead of 5 columns of 256 numbers each!

Any ideas on how to fix this please/

[Jonas]

did you use the second solution? or the first one? i think the second is more appropriate as input for writecell()

if you already used the second solution, can you provide the variable allCokeMask ?

[Jonas]

i tested the code myself now, it works as expected. of course i don't know what you spcified in the further parameters of the writecell() call

headings = {'Pixel Value', 'R', 'G', 'B', 'Grey'};
pixelValue = (0:255)';
allCokeMask=randi(255,100,100,3);
allCoke_R = imhist(allCokeMask(:,:,1));
allCoke_G = imhist(allCokeMask(:,:,2));
allCoke_B = imhist(allCokeMask(:,:,3));
allCokeGrey = imhist(rgb2gray(allCokeMask));
dataCollectionAllCoke = [headings; num2cell([pixelValue, allCoke_R, allCoke_G, allCoke_B, allCokeGrey])];
writecell(dataCollectionAllCoke, 'test.xls'); 

[Teshan Rezel]

@Jonas this works, thank you!