Vector output from a for loop

Hello everyone,

I have an hourly temperature data which covers 8760 values inside a vector. The TMP shows the temperature values however the values below in the code is just for example since i can't put 8760 values here.

I want to get PGRED results as a vector output too. However, when i run the code, although it calculates PGRED values for all TMP values, i get an answer only for the last TMP value which is 36 in this case. My question is, how can i get all the PGRED answers inside 1 vector.

Thank you for your help in advance.

for TMP =[12, 3, 36]
         
    if TMP < 9 
    PGRED=0
   
elseif 9<=TMP & TMP<10
    PGRED= TMP-9
    
elseif 10<=TMP & TMP<28
    PGRED= 1
    
elseif 28<=TMP & TMP<40
    PGRED= -0.083*TMP + 3.33
   
else 40 >= TMP
    PGRED=0
  
    end   
end

Answer 1

[Raj]

TMP =[12, 3, 36];
PGRED=zeros(size(TMP));
for ii=1:length(TMP)
         
    if TMP(ii) < 9 
    PGRED(ii)=0;
   
elseif 9<=TMP(ii) && TMP(ii)<10
    PGRED(ii)= TMP(ii)-9;
    
elseif 10<=TMP(ii) && TMP(ii)<28
    PGRED(ii)= 1;
    
elseif 28<=TMP(ii) && TMP(ii)<40
    PGRED(ii)= -0.083*TMP(ii) + 3.33;
   
else %40 >= TMP(ii) % this condition is not required. Just give a default condition.
    PGRED(ii)=0;
  
    end   
end

Answer 2

[Walter Roberson]

TMP_values = [12, 3, 36];
num_TMP = length(TMP_values);
PGRED = zeros(1, num_TMP);
for TMP_idx = 1 : num_TMP
    TMP = TMP_values(TMP_idx);
    if TMP < 9
        PGRED(TMP_idx) = 0;
    elseif 9<=TMP & TMP<10
        PGRED(TMP_idx) = TMP-9;
    elseif 10<=TMP & TMP<28
        PGRED(TMP_idx) = 1;
    elseif 28<=TMP & TMP<40
        PGRED(TMP_idx) = -0.083*TMP + 3.33;
    elseif 40 >= TMP
        PGRED(TMP_idx) = 0;
    else
        error('Unexpected out of range TMP = %f', TMP)
    end   
end

This is not what I would recommend for this situation: I would recommend that you learn how to use logical indexing. However, I do recommend that you learn to use this pattern, of storing all of the values in a vector and indexing over the length of the vector and using the index to store the results.

[Sercan Yalcin]

Thank you for the suggestion, i will check logical indexing out!

Answer 3

[Andrei Bobrov]

TMP = randi([-12,45],30,4);

f = {@(x)0;@(x)x-9;@(x)1;@(x)3.33 - .083*x;@(x)0};
i = discretize(TMP,[-inf,9,10,28,40,inf]);
out = arrayfun(@(x,y)f{y}(x),TMP,i);