How to verify each position equality?

if true
  % code
clc;
clear all;
close all;
A=imread('imagem60.tif');%carrega a imagem 
vector=A(:); %converte a matriz em um vector
C=unique(vector')%torna os valores da matriz unicos , sem repticao
dimentionA = length(vector)%contagem da dimencao do vector de todos os valores da matriz
dimentionC = length(C);%contagem dos valores da matriz que sao distintos
count =0; % contagem iniciada em zero
for (i=1:dimentionC) %matriz de dimensao de valores nao repetidos 
  for (j=1:dimentionA)%matriz de dimensaos de todos os valores 

    end
end

    %code
  end

I have write this code, i have one image and i convert the image matrix in one vector(C), and create a new vector(C) with non repeated values, now I want cont in the original matrix how many times the same value, of the value position in the new vector(V) repeat and index him by the position who was read in the new vector(C)

Answer 1

[Image Analyst]

Just call imhist().

[pixelCounts, grayLevels] = imhist(grayImage);

If you really need (row, column) location for a particular gray level then you can do

[rows, columns] = find(grayImage == theGrayLevelYouWant);