storing The for loop data

How can I stored the for loop data ...for each loop..Its overwriting the previous data .. I am storing in C..But it is taking only last loop by overwriting previous values any inputs how can I do this ...Thank you in Adance ...any improvement in code can someone suggest

clear all

close all

clc

A=xlsread('Compare_All_cases','B1:AB37');

B=[]

for i= 1:12

B=[B;A(i,:)]

end

for i=1:3:12

effi1=(B(i,:)-B((i+1),:))./(B(i,:))*100

effi2=(B((i+1),:)-B((i+2),:))./(B((i+1),:))*100

effi3=(B(i,:)-B((i+2),:))./(B(i,:))*100

C=vertcat(effi1,effi2,effi3);

end

Answer 1

[KSSV]

The below line

A=xlsread('Compare_All_cases','B1:AB37');
B=[]
for i= 1:12
    B=[B;A(i,:)]
end

can be achieved by:

A=xlsread('Compare_All_cases','B1:AB37');
A = A' ;
B = A(:) ;

The rest of the lines:

for i=1:3:12
effi1=(B(i,:)-B((i+1),:))./(B(i,:))*100
effi2=(B((i+1),:)-B((i+2),:))./(B((i+1),:))*100
effi3=(B(i,:)-B((i+2),:))./(B(i,:))*100
C=vertcat(effi1,effi2,effi3);
end 

can be used:

C = cell([],1) ;
count = 0; 
for i=1:3:12
    count = count+1 ;
effi1=(B(i,:)-B((i+1),:))./(B(i,:))*100
effi2=(B((i+1),:)-B((i+2),:))./(B((i+1),:))*100
effi3=(B(i,:)-B((i+2),:))./(B(i,:))*100
C{i}=vertcat(effi1,effi2,effi3);
end 

You can convert the above cell into a amtrix. Read about Cell2mat.

[Prasad Joshi]

Thank you sir

[KSSV]

Or if the size of C is same.

C = zeros([],3) ;
count = 0; 
for i=1:3:12
    count = count+1 ;
effi1=(B(i,:)-B((i+1),:))./(B(i,:))*100
effi2=(B((i+1),:)-B((i+2),:))./(B((i+1),:))*100
effi3=(B(i,:)-B((i+2),:))./(B(i,:))*100
C(i,:) = [effi1,effi2,effi3];
end 

[Prasad Joshi]

Thank you sir ...for more information ...

[Prasad Joshi]

Can you answer this also sir if possible ...if you give hint for that variable / syntax that would also be fine .. thank you in advance sir ..

https://in.mathworks.com/matlabcentral/answers/1646110-scatter-plot-adding-string-in-x-axis