I have a excel file having data at each cell, that is being converted to image, this image is to be partitioned in 4 equal images, now in this image i'll select a area which should tell the data values at that portion

    Amp=xlsread('C:\Users\AMIT\Desktop\CB\excel\4\Cast Billet Amp Data-(4-5).xls');
    Th=xlsread('C:\Users\AMIT\Desktop\CB\excel\4\Cast Billet thickness Data-(4-5).xls');
    Z=Amp(2:1:514,2:1:256); % rows nd columns
    T=Th(2:1:514,2:1:256);  % rows nd columns
    for i=1:1:513
        for j=1:1:255
                if ((Z(i,j)>=60) && (Z(i,j)<=100))   % amp values only in this range
                  A(i,j)=Z(i,j);
                  B(i,j)=T(i,j);
                else
                    A(i,j)=0;
                  B(i,j)=0;
                end
        end
    end

    for i=1:1:513
        for j=125:1:225

            C(i,j)= A(i,j);
            D(i,j)= B(i,j);

        end
    end

    axes('FontSize',20);
    image(C');figure
    axes('FontSize',20);
    imagesc(D');figure

for i=1:1:513
    for j=1:1:255
            if B(i,j)>=6.5 && B(i,j)<=7.0 % this thick range is our area of interest 
              A4(i,j)=C(i,j);
               else
                A4(i,j)=0;
              end
    end
end

% after this I have to section the image of A4 in 4 equal parts 
% in each image where I select I should get the Amp data of that area or point ( like crop)

[AMIT VERMA]

clc
clear
% take data frm xcl and look for selected area
Amp=xlsread('C:\Users\AMIT\Desktop\CB\excel\4\Cast Billet Amp Data-(4-5).xls');
Th=xlsread('C:\Users\AMIT\Desktop\CB\excel\4\Cast Billet thickness Data-(4-5).xls');
%X=Amp(515:514:131584);
%Y=Amp(2:1:514);
Z=Amp(2:1:514,2:1:256);
T=Th(2:1:514,2:1:256);
%axes('FontSize',20);
%image(Y,X,Z');figure
%axes('FontSize',20);
%imagesc(Y,X,T');figure

for i=1:1:513
    for j=1:1:255
            if ((Z(i,j)>=80) && (Z(i,j)<=100))
              A(i,j)=Z(i,j);
              B(i,j)=T(i,j);
            else
                A(i,j)=0;
              B(i,j)=0;
            end
    end
end

for i=1:1:513
    for j=125:1:225

         C(i,j)= A(i,j);
        D(i,j)= B(i,j);

    end
  end

axes('FontSize',20);
image(A');figure
axes('FontSize',20);
imagesc(B');figure

for i=1:1:513
    for j=125:1:225
            if B(i,j)>=6.5 && B(i,j)<=7.0
              A4(i,j)=C(i,j);
               else
                A4(i,j)=0;
              end
    end
end

axes('FontSize',20);

%imagesc(Y,X,A4');figure
imagesc(A4');
ylim([120 225])
% this A4 is to be divided in to parts (4), and then manually select a area and corresponding amplitude value will be given
I am attaching excel files for help

Answer 1

[Image Analyst]

Do you want it divided into quadrants? Or do you want it to be manually specified? And if quadrants, where do you want to divide the rows at, because 513 is not divisible by 2. So do you want 256 rows and then 257 rows, or do you want 257 rows and then 256 rows? Anyway, why can't you use indexing - it's a trivial concept that people learn the first day they start using MATLAB?

upperLeft = A4(1:256, 1:112);
upperRight = A4(1:256, 113:end);
lowerRight = A4(257:end, 1:112);
lowerLeft = A4(257:end, 113:end);

If you want a demo to get a box region, I've attached a couple of demos.

[AMIT VERMA]

I've tried that , it shows 'green image' when you plot upperLeft,lowerright

[AMIT VERMA]

sorry buddy, it worked ... I behave dumb sometimes Now in these images wherever I select the value of that region should be displayed Just like demo that you posted when I select that area I want amplitude/amplitudes for corresponding points these amplitudes are in that amplitude excel files

[AMIT VERMA]

you can see that selected area I want to know white patch's Amplitude (from cast billet amplitude excel file)